Question

Which equation has x equals 9 as a solution
4+x=12 2x=20
x+7=26 5x=45

Answer 1

5x=45

Explanation:

Solve: 4+x=12

~ Subtract 4

~ x = 8

~ (not nine)

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Solve: 2x=20

- Divide by 2 (isolate x)

- x = 10

- (not nine)

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Solve: x+7=26

~ Subtract 7

~ x = 19

~ (not nine)

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Solve: 5x=45

- Divide by 5 (isolate x)

- x = 9

- (Nine! Our answer)