7th Grade Math

376 Linear Functions

Text Option Take the Quick Check below. Refer to the Quick Review for help.

You have two options for checking

prerequisite skills for this chapter.

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for the Chapter?for the Chapter?

Online Option Take the Online Readiness Quiz.

Evaluate each expression if a = 4,

b = 10, and c = 8.

1. a + b + c 2. bc - ac


2. b + ac 4. 4 c + 3 b


3. 2 b - (a + c) 6. 2 c - b + a

Evaluate each expression if x = 2, y = 5,

and z = - 1.

7. x + 12 8. z + (-5)


8. 4 y + 8 10. 10 + 3 z


9. (2 + y)9 12. 6(x - 4)


10. 3 xy 14. 2 z + y

EXAMPLE 1

Evaluate 3rt - s if r = 3, s = - 4, and

t = 4.

3 rt - s Write the expression.

= 3 (3)(4) - (-4) Substitute.

= 36 - (-4) Multiply.

= 36 + 4 To subtract -4, add 4.

= 40 Add.

Use the coordinate grid to name the point

for each ordered pair.

y

1234 x

4

3

2

1

• 2


• 3


• 4


• 4 - 3 - 2 - 10

"

(

$

%

#

'

15. (-3, 0)


16. (3, -2)


17. (-4, -2)


18. (0, 4)


19. (4, 5)


20. (4, 0)

EXAMPLE 2

Graph and label the point P(-3, 4).

Start at the origin. The first number in the

ordered pair is the distance to the left or

right on the x-axis. Since the number is

• 3, move three units to the left.
  The second number in the ordered pair is
  the distance up or down on the y-axis.
  Since the number is 4, move up four units.
  y

12 3 4x

4

3

2

1

• 2


• 3


• 4


• 4 - 3 - 2 - 10

1

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