10(1+3x)=-20 and -5x-8(1+7x)=-8 With steps

Mathematics

1 answer:

SOVA2 [1]3 years ago

6 0

(1)

10(1+3x)=-20

Cross multiply.

10+30x=-20

Isolate x on one side. So you would subtract 10 on each side. and one side will cross each other out. leaving you with,

30x=-20-10

Subtract 10 from -20.

30x=-30

Divide each side by 30 to get x.

30x÷30=-30÷30

Therefore,

x=-1

(2)

-5x-8(1+7x)=-8

Cross multiply -8(1+7x)

-5x-8-56x=-8

Isolate all x's on one side. So you would add 8 on each side. and one side will cross each other out. leaving you with,

-5x-56x=-8+8

Add 8 to -8.

-5x-56x=0

Subtract -56x from -5x

-61x=0

Divide each side by -61

-61x÷-61=0÷-61

Therefore,

x=0

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