temp a1.notebook
1.
February 04, 2014
7x - y = 10
x = 2y - 6
Oct 20­11:09 AM
Feb 4­8:20 AM
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temp a1.notebook
February 04, 2014
Feb 4­8:44 AM
Feb 4­8:45 AM
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temp a1.notebook
February 04, 2014
What is the resulting equation when the second equation
in the system is substituted into the first equation?
A.
B.
C.
D.
6x - 4y = 11
y = 3x - 2
6x + 8 = 11
-6x - 2 = 11
-6x - 8 = 11
-6x + 8 = 11
Oct 2­8:32 AM
To use substitution, you first select an equation and
solve it for a variable. What is the logical choice for
this system?
5x + 3y = 45
A. first equation for x
B. first equation for y
C. second equation for x
D. second equation for y
x - 6y = 40
Oct 2­8:35 AM
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temp a1.notebook
February 04, 2014
SOLVE:
Dec 5­11:11 AM
sec. 7.3: Solve by Elimination
ex. solve by elimination
2x + 5y = -1
3x - 5y = 11
you need one variable
to have OPPOSITE
coefficients
ADD the equations
SOLVE the new equation
Use that solution to
solve for the other
variable
Oct 20­3:04 PM
4
temp a1.notebook
February 04, 2014
solve by elimination
ex.
3x - 4y = 10
-3x + 7y = -13
Oct 20­3:11 PM
Oct 2­7:56 AM
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