Question

-5x-18y=-28 and -10x+9y=-11 solve elimination

Answer 1

Answer:

$\mathrm{The\:solutions\:to\:the\:system\:of\:equations\:are:}$

$x=2,\:y=1$

Step-by-step explanation:

Given the equations

$-5x-18y=-28$

$-10x+9y=-11$

solving the system of the equation by elimination method

$\begin{bmatrix}-5x-18y=-28\\ -10x+9y=-11\end{bmatrix}$

$\mathrm{Multiply\:}-5x-18y=-28\mathrm{\:by\:}2\:\mathrm{:}\:\quad \:-10x-36y=-56$

$\begin{bmatrix}-10x-36y=-56\\ -10x+9y=-11\end{bmatrix}$

$-10x+9y=-11$

$-$

$\underline{-10x-36y=-56}$

$45y=45$

$\begin{bmatrix}-10x-36y=-56\\ 45y=45\end{bmatrix}$

solve 45y=5 for y:

$45y=45$

$\frac{45y}{45}=\frac{45}{45}$

$y=1$

$\mathrm{For\:}-10x-36y=-56\mathrm{\:plug\:in\:}y=1$

solve $-10x-36\cdot \:1=-56$ for x:

$-10x-36\cdot \:1=-56$

$-10x-36=-56$

Add 36 to both sides

$-10x-36+36=-56+36$

$-10x=-20$

$\frac{-10x}{-10}=\frac{-20}{-10}$

$x=2$

$\mathrm{The\:solutions\:to\:the\:system\:of\:equations\:are:}$

• $x=2,\:y=1$