How do you solve the following system?: $- 8 x - 5 y = 13, - 7 x + y = - 2$ $-8x -5y =13, -7x +y = -2$

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Answer 1 · 2015-12-26T08:31:55

The solution for the system of equations is

$x = - \frac{3}{43}, y = - \frac{107}{43}$ $color(blue)(x=-3/43,y=-107/43$

$- 8 x - 5 y = 13$ $-8x-color(blue)(5y)=13$ ..........equation $(1)$ $(1)$

$- 7 x + y = - 2$ $-7x+y=-2$ , multiplyting by $5$ $5$

$- 35 x + 5 y = - 10$ $-35x+color(blue)(5y)=-10$ ..equation $(2)$ $(2)$

Solving by elimination.

Adding equations $1$ $1$ and $2$ $2$

$-8x-cancelcolor(blue)(5y)=13$

$-35x+cancelcolor(blue)(5y)=-10$

$-43x=3$

$color(blue)(x=-3/43$

Finding $y$ by substituting $x$ in equation $2$ :
$-7x+y=-2$

$-7 xxcolor(blue)((-3/43))+y=-2$

$21/43+y=-2$

$y=-2- 21/43$

$y=-86/43- 21/43$

$color(blue)(y=-107/43$

How do you solve the following system?: -8x -5y =13, -7x +y = -2−8x−5y=13,−7x+y=−2-8x -5y =13, -7x +y = -2