solve for v

v = - 4

iso;ate 3v by subtracting 5 from both sides of the equation

- 12 = 3v ( divide both sides by 3 )

v = = - 4

-7 = 5 + 3v

-7 + (-5) = 3v

-12 = 3v

v = -12 : 3

v = -4

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