How to solve system of equations khan academy?

You can use the elimination method.

You can have y crossed out so you can solve for x and then have x crossed out to solve for y for instance:

X - y = 8
+
X +y =4

To have y gone we have to make it equal to y - y or in this case -y + +y
So
X - y = 8
+
X + y = 4

2x = 12
———-
2. 2

X=6

Now to find y we have x crossed out.

X-y=8
X+y=4

To have x crossed out we’d do x - x
So

X-y = 8
-
X+ y = 4

-2y = 4
————-
-2. -2

Y = -2

Since coordinates go like (x,y) the system of equations for this problem is (6, -2)

The sum is 2,160, no problem