Sometimes, you'll have to make adjustments to both equations to get something to drop out. When possible, always go after the easier numbers!
Let's do this one:
We want to make these 10x and -10x:
Remember to hit each guy!
* It's easy to forget the last guys.
Let's stick y = 0 into the first equation:
The answer is (4, 0).
Solve by elimination:
* Use your head... Which numbers are easier?