Math 10C: Solve a System by Substitution

Note: at 09:21, for example e), the y-coordinate to the solution IS +8. y=-2+10=+8 I apologize for that error in the first method of solving that example.
1. Introduction: 00:04
2. Examples: 00:38
a) Verification on a TI graphing calculator: 08:16
3. Application: 11:29