# need help for simultaneous equation

• August 23rd 2009, 11:36 PM
fvaras89
need help for simultaneous equation
the two equations are

-2x -5y =21

9x -7y = -65

I have tried all methods and i keep getting different answers, could somebody help me?
• August 23rd 2009, 11:48 PM
red_dog
$\left\{\begin{array}{ll}-2x-5y=21\\9x-7y=-65\end{array}\right.$

Multiply the first equation with 9 and the second with 2:

$\left\{\begin{array}{ll}-18x-45y=189\\18x-14y=-130\end{array}\right.$

$-59y=59\Rightarrow y=-1$