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PLEASE HELP ME PLEASE I DON’T UNDERSTAND

PLEASE HELP ME PLEASE I DON’T UNDERSTAND-example-1
User ToFi
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1 Answer

2 votes

Explanation:

remember, when you multiply 2 expressions, you need to multiply every term of one expression with every term of the other expression and then add the results up (while considering their individual signs, of course).

1)

2(s + 8) = -(4s + 2)

2×s + 2×8 = -4s + -2

2s + 16 = -4s - 2

6s + 16 = -2

6s = -18

s = -3

2)

-(8 - 7b) = 6(2 + b)

-8 - -7b = 6×2 + 6×b

-8 + 7b = 12 + 6b

-8 + b = 12

b = 20

3)

6(4x - 11) = 9 - x

6×4x - 6×11 = 9 - x

24x - 66 = 9 - x

25x - 66 = 9

25x = 75

x = 3

4)

-5(4 - x) = 2(-x - 3)

-5×4 - -5×x = 2×-x - 2×3

-20 + 5x = -2x - 6

-20 + 7x = -6

7x = 14

x = 2

5)

-6(y - 1) = 4(9 + y)

-6×y - -6×1 = 4×9 + 4×y

-6y + 6 = 36 + 4y

-10y + 6 = 36

-10y = 30

y = -3

6)

7(2s + 6) = 5(s - 6)

7×2s + 7×6 = 5×s - 5×6

14s + 42 = 5s - 30

9s + 42 = -30

9s = -72

s = -8

7)

z + 4 = 8(-z + 5)

z + 4 = 8×-z + 8×5

z + 4 = -8z + 40

9z + 4 = 40

9z = 36

z = 4

8)

-2(3 + 5x) + 3(1 - x) = 10

-2×3 + -2×5x + 3×1 - 3×x = 10

-6 - 10x + 3 - 3x = 10

-3 - 13x = 10

-13x = 13

x = -1

User John Stoneham
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