I think I'm doing the steps right but I'm not turning out with the right answer.. ): help?

$\displaystyle 2a-7b=-12 and -a+4b=7$

Substituting method is the way im doing it.

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- Dec 14th 2010, 05:00 PMsimoonluSystems of equations
I think I'm doing the steps right but I'm not turning out with the right answer.. ): help?

$\displaystyle 2a-7b=-12 and -a+4b=7$

Substituting method is the way im doing it. - Dec 14th 2010, 05:02 PMdwsmith
$\displaystyle 2a-7b=-12$

$\displaystyle -a+4b=7\Rightarrow a=4b-7$

$\displaystyle 2(4b-7)-7b=-12$

$\displaystyle 8b-14-7b=-12$

$\displaystyle b=2$