Download 7.2 Student Notes - Bismarck Public Schools

Solving Systems
Lesson 7.2: Substitution
Notes
Name:
Date:
Pd:
Example #1. y= 4x
3x+y=-21
Steps:
1. Solve for one variable in one equation.
2. Substitute for that variable in the other equation.
3. Solve.
4. Replace to find the other variable.
5. Check your solution.
In Class EXAMPLES:
1.
x + y = 10
5x – y = 2
2.
y = 2x - 2
2x + 3y = 10
3.
2a – 3b = 7
2a – b = 5
6.
2x + y = 10
x – 3y = -2
You try the following systems: USE SUBSTITUTION.
4.
x=y-6
2x + 3y = 33
5.
t = 2s - 3
s+t=9