Question

Use Elimination to solve this problem:-4x+2y=-124x+8y=-24

Answer 1

$\begin{gathered} -4x+2y=-12 \\ 4x+8y=-24 \end{gathered}$

we add the two equations to eliminate the variable x

$\begin{gathered} -4x+2y=-12 \\ 4x+8y=-24 \\ ----------- \\ 0x+10y=-36 \end{gathered}$

now solve y

$\begin{gathered} 10y=-36 \\ y=-\frac{36}{10} \\ \\ y=-\frac{18}{5} \end{gathered}$

now we can reaplce y on any equation to solve x, i will replace on the first equation

$-4x+2(-\frac{18}{5})=-12$

do the operations on solve for x

$\begin{gathered} -4x-\frac{36}{5}=-12 \\ \\ -4x=-12+\frac{36}{5} \\ \\ -4x=-\frac{24}{5} \\ \\ x=\frac{\frac{24}{5}}{4} \\ \\ x=\frac{6}{5} \end{gathered}$

so, the solution point is

$(\frac{6}{5},-\frac{18}{5})$