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PLEASE HELP ME PLEASE I DON’T UNDERSTAND

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

24 votes
24 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 Hardik Trivedi
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2.9k points