solving an equation by factoring

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Need help solving an equation by factoring.

PROBLEM: $3v^2-10v-12 = -28v + 36$

This is my solution, but it seems a little too much for school:

$3v^2+18v-48 = 0$

$3(v^2+18v-48) = 0$

$3((-1v + -8)(-1v + 2)) = 0$

$-1v + -8 = 0$

$v = -8$

$-1v + 2 = 0$

$v = 2$

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Your algebra went astray: from $3v^2-10v-12=-28v+36$ you should get

$$3v^2+18v-48=0\;.$$

Then you can factor out the $3$ to get $3(v^2+6v-16)=0$, so $v^2+6v-16=0$, and this then factors nicely to give you $(v+8)(v-2)=0$.

You actually made compensating errors, since $3(v^2+18v-48)$ does not factor as

$$3\big((−1v+−8)(−1v+2)\big)\;;$$

your $$3\big((−1v+−8)(−1v+2)\big)=0$$ is actually equivalent to

$$3(v+8)(v-2)=0\;,$$

which is essentially what I got.