1. Algebra 1
7.2 Solving Linear Systems by Substitution
What does substitution mean?
Solving by Substitution
1. Solve one of the equations for one of its _______________________.
2. __________________________ the expression from step 1 into the other
equation.
3. Solve for the other variable.
4. Substitute the _______________________ back into the first equation and solve.
EX1: Solve the linear system.
−x + y = 1
2x + y = - 2
EX2: Solve the linear system.
Note: It is easiest to solve for the variable that doesn’t have a _____________________.
2x + 2 ψ= 3
ξ − 4 ψ= −1
HW p. 408 (18 – 34 even)