Question

Solving system of equations by elimination -2x-9y=-25 and -4x-9y=-23

Answer 1

just try to subtract the second equation from the first equation
(-2x-9y)-(-4x-9y) = -25 - (-23)

Answer 2

\(\large \begin{array}{llll}
-2x-9y=-25 &{\color{red}{ \times -2}}\implies &\quad \cancel{4x}+18y=+50\\
-4x-9y=-23&& \cancel{-4x}-9y=-23\\
\hline\\
&&\qquad\quad \square y=\square
\end{array}\)

Answer 3

times negative 2 to the first equation and it will equal 4x+18y=50. Then you cross out the x's and you solve for y.