Simple....
you have:

To solve for x:

1.) Isolate the variable "x" (Remove y)

Leaving you with....

2.) Divide by the variable.....

Leaving you with...
x=

Now, solve for y.
To solve for y:

1.)Isolate the variable "y" (Remove x)

Leaving you with....

2.)Divide by the variable.....

Leaving you with....
y=

x-intercept: (-20,0)
y-intercept: (0,18)
Thus, your answer.