Chapter 6.2, Problem 21PPS

To determine

To find: Values of x and y.

Answer to Problem 21PPS

  $\begin{array}{l}x=2\\ y=0\end{array}$

Explanation of Solution

Given information:

  $\begin{array}{l}2x+y=4\\ -2x+y=-4\end{array}$

  $2x+y=4$

  $\Rightarrow y=4-2x$ ----(1)

  $-2x+y=-4$ ------(2)

Substitute the value of $y$ from equation-(1) in equation-(2)

We get

  $\begin{array}{l}y=4-2x\\ -2x+y=-4\\ \Rightarrow -2x+4-2x=-4\\ \Rightarrow -2x-2x=-4-4\\ \Rightarrow -4x=-8\\ \Rightarrow x=\frac{-8}{-4}\\ \Rightarrow x=2\end{array}$

Substitute value of $x$ in equation-(1)

We get

  $\begin{array}{l}y=4-2x\\ \Rightarrow y=4-2\left(2\right)\\ \Rightarrow y=4-4\\ \Rightarrow y=0\end{array}$

Therefore, values of x and y are

  $\begin{array}{l}x=2\\ y=0\end{array}$