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

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Answer 1 · 2016-11-29T06:10:05

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

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

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

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

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

$2 x - 5 x - 5 = 10$ $2x-5x-5=10$

$- 3 x - 5 = 10$ $-3x-5=10$

Add $5$ $5$ to each side.

$- 3 x = 15$ $-3x=15$

Divide each side by $3$ $3$ .

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

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