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Solve the following system of equations using elimination (Do not multipy)

1) 5x - 6y = -32
3x + 6y = 48

2) -3x - 3y = 9
3x - 4y = 5

2 Answers

2 votes
1) 5x-6y=-32
3x+6y=48
5x+3x=8x
-32+48=16
16/8= 2
2) -3x-3y=9
3x-4y=5
-3y-4y=-7
9+5=14
14/-7= -2
User Regis May
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7.4k points
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1) 5x - 6y = -32 --> equation 1
3x + 6y = 48 --> equation 2
eliminating y from both of the equations and adding the rest of the terms
we get,
8x = 16
dividing 8 on both sides
x = 2
Substituting the value of x in equation 1
5(2) - 6y = -32
10 - 6y = -32
-6y = -12 ( dividing both sides by -6)
y = 2

2)
-3x - 3y = 9 ---> equation 1
3x - 4y = 5 --> equation 2
eliminating x from both equations and adding the rest of the terms
we get,
-7y = 14 ( dividing both sides by -7 )
y = -2
Substituting the value of y in the equation 1
-3x - 3(-2) =9
-3x + 6 = 9 (subtracting both sides by -6)
-3x = 3
x = -1

Hope this helps you.. :)
User RDU
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7.2k points