Graphing a system of equaton: x + y + 2 = 0, x = y - 8

[Connie]

I don't know how to solve a system of equations graphically. My system is as follows:

. . .x + y + 2 = 0

. . .x = y - 8

 

[mts]

Hello Connie

Here is one way.

Find the co-ordinates of the x and y-intercepts of the two graphs.


x=y-8

Subtract y from both sides

x - y = -8

When x = 0, then y = 8

You have the point (0,8)

When y = 0, then x = -8

You have the point (-8,0)

Plot the two points and draw a line through them.


Do the same for, x+y+2=0


Subtract 2 from both sides

x + y = -2

Find the co-ordinates of the x and y intercepts, as above.

Plot the points and draw a line through them. The co-ordinates of the point of intersection of the two lines is the solution to the system.