How do you solve the system $2x - 2y=5$ and $5x + 2y=9$ ?

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Answer 1 · 2015-06-07T11:28:10

$2x - cancelcolor(blue)(2y)=5$ ........equation $(1)$

$5x + cancelcolor(blue)(2y)=9$ ..........equation $(2)$

Adding equations $(1)$ and $(2)$ we can eliminate $color(blue)(2y)$

$7x = 9 +5$

$7x = 14$

$color(blue)( x = 2$

Substituting $x$ in equation $(1)$

$2x - 2y=5$
$4 - 2y=5$
$4 - 5 = 2y$
$2y = - 1$
$color(blue)(y = -1/2$

The solutions for the system of equations are:
$color(blue)(x =2, y =-1/2$

How do you solve the system 2x - 2y=52x - 2y=5 and 5x + 2y=95x + 2y=9?