Chapter 13.6, Problem 25WE

To determine

To solve: the equation algebraically then draw the graph and also label the intersection point.

Answer to Problem 25WE

The value of $x=1$ and $y=2$ and the intersection point is $\left(1,2\right)$ .

Explanation of Solution

Given information: The equation is:

  $\begin{array}{l}x+y=3\\ x-y=-1\end{array}$

Calculation:

  $\begin{array}{l}x+y=3\mathrm{......}\left(1\right)\\ x-y=-1\mathrm{......}\left(2\right)\\ x=3-y\mathrm{......}\left(3\right)\end{array}$

Put value of $x$ in equation $\left(2\right)$

  $\begin{array}{l}3-y-y=-1\\ -2y=-1-3\\ -2y=-4\\ y=\frac{-4}{-2}\\ y=2\end{array}$

Put value of $y$ in equation $\left(3\right)$

  $\begin{array}{l}x=3-y\\ x=3-2\\ x=1\end{array}$

The graph will be:

  

The intersection point is $\left(1,2\right)$