How do you solve the following system: $-2x + 5y = 20, 2x – 4y = 8$ ?

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Answer 1 · 2015-12-26T08:05:38

The solution for the system of equations is

$color(blue)(x=60, y=28$

$color(blue)(-2x)+5y=20$ .......equation $(1)$

$color(blue)(2x) -4y=8$ .............equation $(2)$

Solving by elimination.
Adding equations $1$ and $2$

$cancelcolor(blue)(-2x)+5y=20$
$cancelcolor(blue)(2x) -4y=8$

$color(blue)(y=28$

Finding $x$ by substituting $y$ in equation $1$

$-2x+5y=20$

$-2x+5 xx color(blue)(28)=20$

$-2x+140=20$

$-2x=20-140$

$-2x=-120$

$x=120/2$

$color(blue)(x=60$

How do you solve the following system: -2x + 5y = 20, 2x – 4y = 8-2x + 5y = 20, 2x – 4y = 8?