Solving two equations at once by graphing, substitution and elimination — plus the word problems that always appear on tests.
Short answers to the things students ask most about this unit.
Use substitution when one equation is already solved for a variable, or easily can be. Use elimination when the equations are both in standard form and coefficients line up.
The lines are parallel — same slope, different intercept — so they never cross. If both equations describe the same line, there are infinitely many solutions instead.
The solutions above show the steps. The classes teach how to think about the problem in the first place — interactive, and worked through at the student’s own pace. Try 3 complete classes free — no payment required to begin.
Try 3 Classes Free →