MathBored

Virginia SOL Mathematics Textbook

Algebra 1 Workbook — Chapter 5: Linear Functions: Characteristics and Forms

SOL A.F.1 (a, b, c) · Companion to Textbook Chapter 5

Each page below is one Canva page. Headings are sized for direct paste: page title as H1, section labels as H2. Figures referenced by filename live in ../figures/. Every numbered item is the same problem as in the textbook, so one answer key serves both. Item numbers run continuously from 1 to 124.


PAGE 1 — Chapter opener

Chapter 5 · Linear Functions: Characteristics and Forms

Standard A.F.1 (a, b, c)

In this chapter you will:

Words to know: linear function · slope · rate of change · rise · run · yy-intercept · xx-intercept · zero · domain · range · parent function · transformation · reflection · vertical shift · slope-intercept form · standard form · point-slope form

Convention: an intercept is a point, written (0,b)(0,b) or (a,0)(a,0). A zero is a number. The zero is the xx-coordinate of the xx-intercept.


PAGE 2 — Domain and range of a line

5.1 Domain and Range of a Linear Function

FIGURE: fig1-domain-range-of-a-line.png (full width)

Fill in the blanks.

For a linear function with a nonzero slope, the domain is ____________________ and the range is ____________________.

The arrowheads on the ends of a drawn line say the graph ____________________ past the edge of the grid.

  1. f(x)=2x4f(x) = 2x - 4 Domain: _______________________ Range: _______________________

  2. What do the two arrowheads tell you that the drawn portion does not?



PAGE 3 — The two special lines

Horizontal and Vertical

FIGURE: fig2-horizontal-line-domain-range.png (full width)

Complete the frame. A horizontal line has slope m=m = ______. Its range is ______________________ and it has ______ zero. (one / no)

A vertical line x=ax = a ______ a function, and its slope is ____________________. (is / is not)

  1. The line y=3y = 3 Domain: _______________________ Range: _______________________

  2. Is x=2x = -2 a function? ______ What goes wrong?


    Why does it have no slope? _______________________________________

  3. y=4y = -4 Domain: _______________________ Range: _______________________

  4. Is x=5x = 5 a function? ______ Its slope: ____________________


PAGE 4 — When the story cuts the domain down

Domain in a Real Situation

FIGURE: fig3-context-domain-and-range.png (full width)

Three questions to ask of any context.

Can the input be ____________? Can the input be a ____________? Where does the story ____________?

  1. V(x)=2x+8V(x) = -2x + 8 Domain: _______________ Range: _______________

  2. Why is the domain not all real numbers, even though the domain of the equation is?


  3. Apply it. State the domain and the range, then say what each means about the cooler, with units.

    Domain means _______________________________________

    Range means _______________________________________


PAGE 5 — Practice · domain and range

Practice · Both Sets

  1. Give both sets.
Function Domain Range
a) f(x)=5x+1f(x) = -5x + 1
b) g(x)=14x2g(x) = \tfrac14 x - 2
c) h(x)=7h(x) = 7
d) y=xy = x
  1. Apply it. A candle is 1212 in. tall and burns down 1.51.5 in. per hour: H(t)=121.5tH(t) = 12 - 1.5t.

    Domain: _______________ Range: _______________

    What fixes each endpoint? _______________________________________

  2. Apply it. A shuttle van charges $2.50 per passenger and seats at most six.

    Domain: _______________________ Range: _______________________

    Why is the graph dots, not a segment? _______________________________________

  3. Explain. Why is the range of a linear function with a nonzero slope always all real numbers?


  4. Find the error. A student says the range of f(x)=2x4f(x) = 2x - 4 is "all real numbers greater than 4-4."

    What went wrong? _______________________________________________

    Correct range: _______________________


PAGE 6 — Exit ticket 5.1

Exit Ticket · Lesson 5.1

Name: ________________________ Date: ____________

  1. f(x)=3x+11f(x) = -3x + 11 Domain: _______________ Range: _______________

  2. Explain. How does the domain of a line drawn with arrowheads differ from the domain of a segment with two filled-in endpoints?



PAGE 7 — Slope and the two intercepts

5.2 Slope and the Two Intercepts

FIGURE: fig4-slope-and-intercepts.png (full width)

Complete the formulas.

m==y2y1m = \dfrac{\underline{\hspace{2cm}}}{\underline{\hspace{2cm}}} = \dfrac{y_2 - y_1}{\underline{\hspace{2cm}}}

In y=mx+by = mx + b: the slope is ______ and the yy-intercept is the point ____________.

A positive slope ____________ from left to right; a negative slope ____________.

  1. f(x)=34x3f(x) = \tfrac34 x - 3 Slope: ______ yy-intercept: ____________ xx-intercept: ____________

  2. What do "rise 33" and "run 44" tell you, and how do they produce the slope?


  3. The graph crosses the yy-axis at ____________, so b=b = ______


PAGE 8 — Practice · finding slope

Practice · Slope

  1. Through (1,2)(-1, 2) and (3,10)(3, 10): m=m = ______

  2. Through (2,7)(2, 7) and (6,1)(6, 1): m=m = ______

  3. y=5x+8y = -5x + 8 Slope: ______ yy-intercept: ____________

  4. Read each equation.

Equation Slope yy-intercept
a) y=4x9y = 4x - 9
b) y=23x+5y = -\tfrac23 x + 5
c) y=xy = x
d) y=7y = -7
  1. Find each slope.
Two points Slope
a) (0,3)(0,3) and (4,11)(4,11)
b) (2,5)(-2,5) and (1,4)(1,-4)
c) (6,1)(-6,-1) and (2,1)(2,-1)
d) (3,4)(3,4) and (3,9)(3,9)

PAGE 9 — Practice · intercepts

Practice · Both Intercepts

Frame. To find the xx-intercept, set ______ equal to 00 and solve for ______.

  1. y=5x10y = 5x - 10 yy-intercept: ____________ xx-intercept: ____________

  2. y=14x+3y = -\tfrac14 x + 3 yy-intercept: ____________ xx-intercept: ____________

  3. A table lists xx: 0,1,2,30, 1, 2, 3 and yy: 5,1,3,7-5, -1, 3, 7.

    Slope: ______ How you got it: _______________________________________

    yy-intercept: ____________ How you got it: _______________________________

  4. Find the error. A student reads y=32xy = 3 - 2x as slope 33 and yy-intercept (0,2)(0,-2).

    What went wrong? _______________________________________________

    Correct slope: ______ Correct yy-intercept: ____________


PAGE 10 — Slope and intercept in context

What the Two Numbers Mean

  1. Apply it. A phone plan costs C(m)=0.05m+20C(m) = 0.05m + 20 dollars for mm minutes.

    The slope 0.050.05 means _______________________________________

    The yy-intercept (0,20)(0,20) means _______________________________________

  2. Apply it. A tank drains: W(t)=24015tW(t) = 240 - 15t gallons after tt minutes.

    Slope means _______________________________________

    yy-intercept means _______________________________________

    xx-intercept: ____________ It means _______________________________________


PAGE 11 — Exit ticket 5.2

Exit Ticket · Lesson 5.2

Name: ________________________ Date: ____________

  1. y=12x+6y = -\tfrac12 x + 6 Slope: ______ yy-intercept: ____________

  2. Through (3,8)(-3, 8) and (5,4)(5, 4): m=m = ______

  3. y=3x+12y = 3x + 12 yy-intercept: ____________ xx-intercept: ____________

  4. Apply it. T(x)=8x+45T(x) = 8x + 45 dollars for xx tickets in one order.

    Slope means _______________________________________

    yy-intercept means _______________________________________


PAGE 12 — The zero

5.3 The Zero of a Linear Function

FIGURE: fig5-zero-of-a-linear-function.png (full width)

Complete the frame. Three names for one fact:

the zero of ff is the input with output ______ · the xx-intercept is the point ____________ · the solution of the equation ____________________

A zero is a ____________. An xx-intercept is a ____________. (number / point)

  1. f(x)=2x+6f(x) = -2x + 6 Zero: ______ Point that names it: ____________

  2. Why is f(3)=0f(3) = 0 the same statement as "the graph passes through (3,0)(3,0)"?


  3. f(x)=4x20f(x) = 4x - 20 Zero: ______

  4. g(x)=3x+7g(x) = -3x + 7 Zero: ______

  5. f(x)=34x3f(x) = \tfrac34 x - 3 Zero: ______ How the figure shows it: _______________________

  6. Does y=3y = 3 have a zero? ______ Why? _______________________________________


PAGE 13 — Practice · zeros

Practice · Finding Zeros

  1. Find each zero.
Function Equation to solve Zero
a) f(x)=x9f(x) = x - 9
b) f(x)=5xf(x) = -5x
c) f(x)=2x+7f(x) = 2x + 7
d) f(x)=13x4f(x) = \tfrac13 x - 4
  1. Apply it. B(w)=32040wB(w) = 320 - 40w dollars after ww weeks. Zero: ______

    It means _______________________________________

  2. Apply it. The cooler, V(x)=2x+8V(x) = -2x + 8. Zero: ______

    It means _______________________________________

    Why does the domain of the model end at exactly that input? _______________________________

  3. Find the error. A student says the zero of f(x)=2x10f(x) = 2x - 10 is 10-10.

    What did the student find instead? _______________________

    Correct zero: ______ Correct xx-intercept: ____________


PAGE 14 — Exit ticket 5.3

Exit Ticket · Lesson 5.3

Name: ________________________ Date: ____________

  1. f(x)=6x+18f(x) = 6x + 18 Zero: ______

  2. f(x)=14x+5f(x) = -\tfrac14 x + 5 Zero: ______

  3. Apply it. A drone descends: D(t)=9012tD(t) = 90 - 12t meters after tt seconds.

    Zero: ______ It means _______________________________________

  4. Explain. Why are the zero, the xx-intercept, and the solution of mx+b=0mx + b = 0 the same fact?



PAGE 15 — The parent function

5.4 The Parent Function y=xy = x

FIGURE: fig6-parent-function-y-equals-x.png (full width)

Complete the sentence. In y=xy = x, each output equals its own ____________.

Written as y=mx+by = mx + b, the parent is y=x+y = \underline{\hspace{2cm}}x + \underline{\hspace{2cm}}.

  1. Slope: ______ yy-intercept: ____________

  2. The five marked points: _______________________________________

  3. The triangle shows a rise of ______ over a run of ______, so m=m = ______

  4. Domain: _______________________ Range: _______________________

  5. Zero: ______ Point that carries it: ____________

  6. Explain. What is a parent function, and why is y=xy = x the parent of the linear family?



PAGE 16 — Practice and exit ticket 5.4

Practice · The Parent

  1. Complete the table for y=xy = x.
xx 4-4 2-2 00 55 77
yy
  1. Is (6,6)(-6,-6) on y=xy = x? ______ Is (2,2)(2,-2)? ______ Explain each.


  2. In y=mx+by = mx + b, the parent has m=m = ______ and b=b = ______

  3. Apply it. A club gives one hour of credit per hour volunteered: C(h)=hC(h) = h.

    Slope means _______________________________________

    yy-intercept means _______________________________________

Exit Ticket · Lesson 5.4

  1. For y=xy = x — slope: ______ yy-intercept: ______ zero: ______ domain: ____________ range: ____________

  2. Is (9,9)(-9,-9) on the parent? ______ Why? _______________________________________

  3. Find the error. A student says the parent of the linear family is y=0y = 0.

    What is wrong? _______________________________________ Correct parent: ____________

  4. Explain. What makes y=xy = x the parent, and name one transformation of it.



PAGE 17 — Transformations of the parent

5.5 Transformations of the Parent Function

FIGURE: fig7-transformations-of-the-parent.png (full width)

Two dials. Multiplying xx by a number changes the ____________ and leaves the yy-intercept at ____________.

Adding a constant changes the ____________ and leaves the slope at ______.

If m>1|m| > 1 the line is ____________ than the parent; if 0<m<10 < |m| < 1 it is ____________.

A negative slope reflects the parent across the ______-axis.

  1. Left panel — equations: ____________ and ____________ Slopes: ______ and ______ Shared yy-intercept: ____________

  2. Which is steeper than the parent? ____________ Less steep? ____________ How can you tell?


  3. Middle panel — transformation: ____________________ Slopes: ______ and ______

  4. Right panel — what changed: ____________________ What stayed the same: ____________________


PAGE 18 — Practice · describing transformations

Practice · Against the Parent

  1. y=5xy = 5x — effect on slope: ____________________ effect on yy-intercept: ____________________

  2. y=x7y = x - 7 — effect on slope: ____________________ effect on yy-intercept: ____________________

  3. Describe each as a transformation of y=xy = x.

Function Effect on the slope Effect on the yy-intercept
a) y=8xy = 8x
b) y=x+10y = x + 10
c) y=xy = -x
d) y=12x3y = \tfrac12 x - 3
  1. Steeper: y=4xy = 4x or y=6xy = -6x? ____________ What did you compare? _______________________

  2. Parent with slope multiplied by 3-3, then shifted down 22: y=y = _______________________

  3. Does reflecting the parent across the xx-axis change the yy-intercept? ______ Why?



PAGE 19 — Reasoning about transformations

Why the Dials Are Independent

  1. The parent shifted up 66.

    Slope: ______ yy-intercept: ____________ Equation: ____________ Zero: ______

  2. Complete both rows, then say what the table shows.

xx 2-2 00 44
y=xy = x
y=x+3y = x + 3
What it shows: _______________________________________________
  1. Explain. Why does changing bb never change the slope? Say what happens to every output.


  2. Find the error. A student says y=4xy = -4x is the parent shifted down 44.

    What went wrong? _______________________________________________

    Correct description: _______________________________________


PAGE 20 — Exit ticket 5.5

Exit Ticket · Lesson 5.5

Name: ________________________ Date: ____________

  1. y=7xy = 7x — slope: ______ yy-intercept: ____________ Description: _______________________

  2. y=x9y = x - 9 — slope: ______ yy-intercept: ____________ Description: _______________________

  3. y=12x+4y = -\tfrac12 x + 4 — slope: ______ yy-intercept: ____________ Description: _______________________

  4. Explain. In y=mx+by = mx + b, which number does a slope-changing transformation affect, and which does a vertical shift affect? What does each leave alone?



PAGE 21 — Three forms, one line

5.6 Three Equivalent Forms

FIGURE: fig8-three-forms-one-line.png (full width)

Complete the table.

Form Looks like Hands you for free
Slope-intercept y=y = \underline{\hspace{2cm}}
Standard =C\underline{\hspace{2cm}} = C
Point-slope yy1=y - y_1 = \underline{\hspace{2cm}}
  1. The three equations in the figure:


  2. Which form shows the slope and yy-intercept at a glance? ____________________

    Slope: ______ yy-intercept: ____________

  3. Which form names a point the other two never mention? ____________________ The point: ____________


PAGE 22 — What standard form is good for

Intercepts the Cheap Way

FIGURE: fig9-standard-form-intercepts.png (full width)

Frame. In Ax+By=CAx + By = C, let y=0y = 0 to find the ______-intercept and let x=0x = 0 to find the ______-intercept.

  1. 3x+4y=123x + 4y = 12 xx-intercept: ____________ yy-intercept: ____________

  2. Convert 3x+4y=123x + 4y = 12 to slope-intercept form: _______________________

    Slope: ______ yy-intercept: ____________

FIGURE: fig10-vertical-line-standard-form.png (full width)

  1. Why can x=3x = 3 not be written in slope-intercept form?


    In standard form: _______________________


PAGE 23 — Practice · converting

Practice · Converting Between Forms

  1. Convert to slope-intercept form.
Standard form Slope-intercept form Slope yy-intercept
a) 2x+y=72x + y = 7
b) x3y=9x - 3y = 9
c) 5x2y=85x - 2y = -8
d) 4x+6y=184x + 6y = 18
  1. Convert to standard form with integer coefficients.
Slope-intercept form Standard form
a) y=3x5y = 3x - 5
b) y=x+2y = -x + 2
c) y=12x+4y = \tfrac12 x + 4
d) y=23x+1y = -\tfrac23 x + 1
  1. Convert to slope-intercept form.

    a) y5=3(x2)y - 5 = 3(x - 2): _______________________

    b) y+1=2(x4)y + 1 = -2(x - 4): _______________________

    c) y7=12(x+6)y - 7 = \tfrac12(x + 6): _______________________


PAGE 24 — Practice · reading and checking

Practice · Reading Each Form

  1. From y4=5(x+3)y - 4 = -5(x + 3): slope ______ point ____________

  2. 5x3y=155x - 3y = 15 xx-intercept: ____________ yy-intercept: ____________

  3. 2x+7y=142x + 7y = 14 xx-intercept: ____________ yy-intercept: ____________

  4. Check the point (5,6)(5,6) in all three forms of the same line.

Form Substitution True?
y=2x4y = 2x - 4
2xy=42x - y = 4
y2=2(x3)y - 2 = 2(x - 3)
  1. Find the error. A student converts 3xy=63x - y = 6 and writes y=3x+6y = 3x + 6.

    What went wrong? _______________________________________________

    Correct form: _______________________


PAGE 25 — Forms in context

Choosing a Form

  1. Apply it. Shirts at $4 and hats at $6 toward a $120 goal: 4x+6y=1204x + 6y = 120.

    xx-intercept: ____________ It means _______________________________________

    yy-intercept: ____________ It means _______________________________________

  2. Apply it. A taxi charges $3 to start plus $2.50 per mile.

    Best form: ____________________ Equation: _______________________

    The $3 is the ____________________ The $2.50 is the ____________________


PAGE 26 — Exit ticket 5.6

Exit Ticket · Lesson 5.6

Name: ________________________ Date: ____________

  1. 4xy=104x - y = 10 → _______________________ Slope: ______ yy-intercept: ____________

  2. y=3x+8y = -3x + 8 → standard form: _______________________

  3. y6=4(x1)y - 6 = 4(x - 1) → _______________________

  4. 6x+5y=306x + 5y = 30 xx-intercept: ____________ yy-intercept: ____________


PAGE 27 — Chapter 5 review · domain, range, zeros

Chapter 5 Review

Part A · Domain, range, and zeros

  1. f(x)=7x+2f(x) = -7x + 2 Domain: ____________ Range: ____________ Zero: ______

  2. y=9y = 9 Domain: ____________ Range: ____________ Zero: ______

  3. Is x=1x = -1 a function? ______ Slope: ____________ Why?


FIGURE: fig3-context-domain-and-range.png (half width)

  1. V(x)=2x+8V(x) = -2x + 8 Domain: ____________ Range: ____________ Zero: ______

    Each, in context: _______________________________________________

  2. Apply it. An elevator descends from 4545 m at 33 m per second: E(t)=453tE(t) = 45 - 3t.

    Zero: ______ Domain: ____________ Range: ____________

  3. Explain. Why does a linear function with a nonzero slope have exactly one zero? Which kind has none?



PAGE 28 — Chapter 5 review · slope and intercepts

Chapter 5 Review (continued)

Part B · Slope and intercepts

  1. y=2x6y = 2x - 6 Slope: ______ yy-intercept: ____________ xx-intercept: ____________

  2. Through (4,9)(-4, 9) and (2,3)(2, -3): m=m = ______

  3. y=3x+15y = -3x + 15 yy-intercept: ____________ xx-intercept: ____________

  4. Apply it. A pool fills: G(t)=30t+150G(t) = 30t + 150 gallons after tt minutes.

    Slope means _______________________________________

    yy-intercept means _______________________________________

FIGURE: fig4-slope-and-intercepts.png (half width)

  1. Read all four from the figure, and say which part of the picture gives each.
Characteristic Value Where in the figure
slope
yy-intercept
xx-intercept
zero
  1. Find the error. A student says the xx-intercept of y=4x+8y = 4x + 8 is (0,8)(0,8).

    What went wrong? _______________________ Correct intercepts: ____________ and ____________


PAGE 29 — Chapter 5 review · parent and transformations

Chapter 5 Review (continued)

Part C · The parent function and transformations

FIGURE: fig7-transformations-of-the-parent.png (full width)

  1. y=6x1y = 6x - 1 — slope effect: ____________________ yy-intercept effect: ____________________

  2. y=x+5y = -x + 5 — slope effect: ____________________ yy-intercept effect: ____________________

  3. For each panel, name what changed and what stayed the same.

Panel Changed Stayed the same
left
middle
right
  1. Two transformations with yy-intercept (0,0)(0,0) but different steepness:

    _______________________ and _______________________ Steeper: ____________

  2. Explain. Why is every linear function a transformation of y=xy = x? Which straight line is not covered, and why?



PAGE 30 — Chapter 5 review · three forms

Chapter 5 Review (continued)

Part D · Three equivalent forms

  1. x+4y=8x + 4y = 8 → _______________________ Slope: ______ yy-intercept: ____________

  2. y=5x3y = 5x - 3 → standard form: _______________________

  3. y+2=3(x1)y + 2 = -3(x - 1) → _______________________

  4. 4x5y=204x - 5y = 20 xx-intercept: ____________ yy-intercept: ____________

FIGURE: fig10-vertical-line-standard-form.png (half width)

  1. Which forms can write x=3x = 3? ____________________ Which can write y=2y = -2? ____________________

    The difference: _______________________________________________


PAGE 31 — Chapter 5 review · mixed application

Chapter 5 Review (continued)

Part E · Application

  1. Apply it. A rideshare charges C(m)=1.75m+4C(m) = 1.75m + 4 dollars for mm miles.

    Slope: ______ yy-intercept: ____________ Zero: ______

    Slope means _______________________________________

    yy-intercept means _______________________________________

    Why does the zero have no meaning here? _______________________________________

  2. Apply it. Tickets at $5 and programs at $8 toward $200: 5x+8y=2005x + 8y = 200.

    xx-intercept: ____________ It means _______________________________________

    yy-intercept: ____________ It means _______________________________________

    Slope-intercept form: _______________________

    What that form reveals: _______________________________________


PAGE 32 — Blank grids

Graph Paper

FIGURE: fig11-blank-grids.png (full page)

Use these grids for any sketch a teacher assigns alongside this chapter: plotting the two intercepts of a line you have just found, drawing a slope triangle to check a rate of change, or drawing the parent y=xy = x beside one of its transformations to compare steepness.

Two reminders for every sketch:


Canva production notes