Problem 1
Answer: Choice B) x = -2
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Explanation:
Add the equations straight down.
The x terms add to 5x+(-3x) = 2x
The y terms cancel out since 3y+(-3y) = 0y = 0
The right hand sides add to -7+3 = -3
After adding the equations you should get 2x = -4 which solves to x = -2
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Problem 2
Answer: y = 4
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Explanation:
Since 5x = 0, this means x = 0 after dividing both sides by 5.
Use this to find y
y = -4x+4
y = -4(0)+4
y = 4
If you want the value of z, then
x = -3y+z+6
0 = -3(4)+z+6
0 = z-6
6 = z
z = 6
