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Mr. Sims
Algebra 1
Section 7.9 A
Cumulative Review
Evaluate the expression.
1. 789 – (-72) – 102
= 789 – (- 49) – 100
= 789 + 49 – 100
= 738
2. 8(3  4)  2
62
8(1)  2

36
8 2

36
6

36
1

6
Mr. Sims
Use the distributive property to rewrite the expression
without parentheses.
1
3. 8(2b – 10)
4.  (30  x)5
25
= 16b – 80
1
  (150  5x) multiply (30 – x) by 5 first
25
{distributive property}
1
 6  x
5
distributive property
5. -x(4 – x) + x2
= - 4x + x2 + x2 distributive property
= 2x2 – 4x combine like terms
Mr. Sims
Solve each equation.
-24 -24
7. 2(q – 6) = 14
2q – 12 = 14
x=6
+12 +12
6. x + 24 = 30
distributive property
2q = 26
q = 13
8.
3
(x  1)  12
4
3
3
x   12
4
4
distributive property
+3 +3
4
4
17
4 3
51 4 multiply both sides by 4/3
x

3 4
4 3
x = 17
Mr. Sims
Decide whether the graphs of the two equations are parallel lines.
9. y = 2x – 12
slope = 2
6x + 3y = 0
-6x
not parallel
10. 2x + 3y = 35
-2x
-2x
find slopes {get in slope-intercept form}
-6x
3y = -6x
y = -2x
slope = -2
y = -2 - 2
3x
parallel lines have equal slopes
find slopes {get in slope-intercept form}
3y = -2x + 35
slope = -2
y = -2 + 35
3
3x
3
parallel
slope = -2
3
Mr. Sims
Find the x-intercept and the y-intercept of the graph
of the equation.
11. 6x – 2y = -7
x-intercept
6x – 2(0) = -7
6x = -7
7
x
6
to get x-intercept: put 0 in for y
to get y-intercept: put 0 in for x
y-intercept
6(0) – 2y = -7
-2y = -7
7
y
2
12. - 4x + 5y = -8
x-intercept
y-intercept
- 4x + 5(0) = -8
- 4(0) + 5y = -8
- 4x = -8
5y = -8
x=2
8
y
5
Mr. Sims
Write the equation in standard form of the line that passes
through the point with the given slope.
13. (2,8), m = 9
y = mx + b
8 = 9(2) + b
8 = 18 + b
-18 -18
b = -10
find y-intercept
y = mx + b
y = 9x – 10
get in standard form
-9x -9x
-9x + y = -10
3
14. (0,0), m 
8
y = mx + b
3
0  (0)  b
8
b=0
3
8
-8  x  y  0 no fractions
y = mx + b
3x – 8y = 0
3
y x
8
get in standard form
-3/8x -3/8x
Mr. Sims
Solve each equation.
15. |x + 6| = 10.5
x + 6 = 10.5 or x + 6 = -10.5
-6
-6
x = 4.5
-6
or
-6
x = -16.5
16. 3|2 – x| = 9
|2 – x| = 3
divide both sides by 3
2 – x = 3 or 2 – x = -3
-2
-2
-2
-2
-x = 1
-x = -5
x = -1 or x = 5
Mr. Sims
Algebra 1
Section 7.9 A
Assignment
Evaluate the expression.
1.) (35 ÷ 5) + (49 ÷ 7)
2.) 9 – 42 + (-5)3 ÷ 25
Use the distributive property to rewrite the expression without parentheses.
3.) -2(6 – s)
4.) 9.6(b – 10)
5.) (t + 2)t – t2
7.) 7(x – 1) = 14x – 7
8.)
Solve the equation.
6.) 9r = 89
p
 10  1
2
Decide whether the graphs of the two equations are parallel lines.
9.) y  5 x  1 , 5x – 6y = 36
6
10.) -x + 3.5y = 9 , y = .2857x
Mr. Sims
Find the x-intercept and the y-intercept of the graph of the equation.
11.)
1
x 1 y
4
8
19
2
13.)  x  y  
12.) -y = 12 + 2x
9
3
3
Write the equation in standard form of the line that passes through
the point with the given slope.
14.) (0,5) , m = -1
15.) (6,2) , m   9
10


1 3
16.)  ,  , m  2
4
4
Mr. Sims
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Mr. Sims