How do you solve X for the following equations $2x+5y=10, y=-x-1$ ?

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Answer 1 · 2016-11-29T06:10:05

$x=-5$

$2x+5y=10$
$y=-x-1$

In the first equation, substitute $y$ with $(-x-1)$ .

$2x+5(-x-1)=10$

Open the brackets. The multiplication of negative positive yields a negative.

$2x-5x-5=10$

$-3x-5=10$

Add $5$ to each side.

$-3x=15$

Divide each side by $3$ .

$-x=5$ or $x=-5$

How do you solve X for the following equations 2x+5y=10, y=-x-12x+5y=10, y=-x-1?