Bell Ringer 2
Solve the following system of equations by graphing:
a. x + y = 4
3x + 3y = 12
b. 3x + 2y = 10
2x + 3y = 10
Homework 6.2 due Monday:
Pg. 347 ­ 349 ( 8 ­ 48, every 4th)
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Lesson Objectives:
­ Solve system of equations by using substitution.
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Steps for solving by substitution:
1st ­ Solve one of the equations for one of the variables.
2nd ­ Substitute your new equation into the other equation that you did not use for the variable you solved for. Then solve for the given variable.
3rd ­ Substitute your answer into one of the equations and solve for the other variable.
4th ­ Write the solution as an ordered pair. (x, y)
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Solve by Substitution:
a. y = 2x + 1
3x + y = ­9
b. y = 4x ­ 6
5x + 3y = ­1
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Solve by Substitution:
a. x + 2y = 6
3x ­ 4y = 28
b. 4x + 5y = 11
y ­ 3x = ­13
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No solution or Infinite Solution:
a. y = 2x ­ 1
­6x + 3y = ­12
b. 2x ­ y = 8
y = 2x ­ 3
c. 4x ­ 3y = 1
6y ­ 8x = ­2
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