67.3k views
5 votes
Solve the system by substitution.3x+4y=50 -2x=y

1 Answer

6 votes

we have the following:


\begin{gathered} 3x+4y=50 \\ -2x=y \end{gathered}

replacing:


\begin{gathered} 3x+4\cdot-2x=50 \\ 3x-8x=50 \\ -5x=50 \\ x=-(50)/(5) \\ x=-10 \end{gathered}

now, from y:


\begin{gathered} y=-2\cdot-10 \\ y=20 \end{gathered}

Therefore:

x = -10

y = 20

User Ryan Peschel
by
4.0k points