Question

Solve the system by substitution -×+ 3y = 20 7y = ×

Answer 1

Given, 7y=x.

Hence, substitute 7y for x in equation -x+3y=20.

`\begin{gathered} -x+3y=20 \\ -7y+3y=20 \\ -4y=20 \\ y=-5 \end{gathered}`

Now, substitute y=-5 in 7y=x.

`\begin{gathered} 7*(-5)=x \\ -35=x \end{gathered}`

Therefore, the values of x and y are -35 and -5 respectively.