Transcript Solve the linear system by elimination. Check your solution by

Happy Summer Birthday to:
Dylan Hare
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Step One: Make sure the equations are aligned.
They have to be in standard form.
Step Two: Add/subtract the equations to eliminate
one variable.
Step Three: Solve for the left over variable.
Step Four: Substitute the value into either original
equation to solve for the other variable.
Answer: An ordered pair (x, y).
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1)
Solve the linear system by elimination (adding or subtracting).
Check your solution.
3x + 4y = 8
-3x + 5y = 10
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2)
Solve the linear system by elimination. Check your solution.
2x + 3y = 11
-2x + 5y = 13
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3)
Solve the linear system by elimination. Check your solution.
5x + 6y = 4
7x + 6y = 8
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4)
Solve the linear system by elimination. Check your solution.
4x + 3y = 2
5x + 3y = -2
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5)
Solve the linear system by elimination. Check your solution.
9x – 3y = 18
3y = -7x + 30
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6)
Solve the linear system by elimination. Check your solution.
8x – 4y = -4
4y = 3x + 14
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7)
Solve the linear system by elimination . Check your solution.
3x – 3y = 21
8x + 6y = -14
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8)
Solve the linear system by elimination (adding or subtracting).
Check your solution.
6x + 5y = 19
2x + 3y = 5
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Sometimes when we are solving linear systems,
strange things can happen, and it seems like
we’ve made a mistake.
These things happen when the two lines are
parallel or when they are the exact same line.
It’s obvious when we graph it, but let’s talk
about what happens when we try to solve a
“strange problem” like this by elimination or
substitution.
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9)
Solve the linear system by elimination. Check your solution by
graphing both lines in the calculator.
2x + 4y = 6
x + 2y = 3
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10)
Solve the linear system by elimination. Check your solution by
graphing both lines in the calculator.
y = 2x – 3
y = 2x + 3
So in summary:
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a false statement such as 1 = 8, means the lines are
parallel.
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“no solution”
a true statement, such as 2 = 2, means the lines are
the same line.
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“infinitely many solutions”
11) Yummy bakery sells apple and blueberry pies
each Saturday. Apple pies cost $8 each and
blueberry pies cost $12 each. Last Saturday, the
bakery sold 4 more apple pies than blueberry pies
for total sales of $232. Which system of equations
can be used to find a, the number of apple pies and
b, the number of blueberry pies sold?
A. 8a + 12b = 232
b=a+4
B. 8a + 12b = 232
a=b+4
C. 8a + 12b = 232
a+b=4
D. 8a + 12b = 232
a=b–4
WS