1. Algebra 1
7.2
Chapter 7: Solving Systems of Linear Equations
Section 2: Solving Linear Systems by Substitution Pg. 405 – 410
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Use substitution to solve the system Use a graph to check your solution:
y = x− 3
1.
4 x + y = 32
a.) Solve an equation for a variable (isolate one variable).
b.) Substitute the expression for the variable in part “a” into the other equation and solve for
the other variable.
c.) Substitute the value of your known variable into the first equation and solve for the other
variable.
d.) Write your solution as a coordinate. How can you check the solution?
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x+ y = 9
2.
2x + 5 y = 30
2. Algebra 1
7.2
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3x − y = 0
3.
y= 6
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x + 4 y = 300
4.
x = 2y
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2x + y = − 4
5.
x − 2y = − 7
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