SOLUTION: How can you solve these two equations by substitution? x - 2y = -10 y = -2x

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Question 850460: How can you solve these two equations by substitution?
x - 2y = -10
y = -2x - 6
Found 2 solutions by harpazo, checkley79:
Answer by harpazo(655) (Show Source):
You can put this solution on YOUR website!

x - 2y = -10
y = -2x - 6
------------
x-2(-2x-6) = -10
x+4x+12 = -10
5x+12 = -10
5x = -10-22
x =-32/5
To find y, plug the value of x just found into EITHER original equations given.
I will use y = -2x - 6.
y = -2(-32/5)-6
y = (64/5)-6
Can you finish?
Just continue to simplify for y.

Answer by checkley79(3341) (Show Source):
You can put this solution on YOUR website!
x - 2y = -10 or x=2y-10
y = -2x - 6 substitute (2y-10) for x in this equation & solve for y.
y=-2(2y-10)-6
y=-4y+20-6
y+4y=14
5y=14
y=14/5 ans.
x=2(14/5)-10
x=28/5-10
x=28/5-50/5
x=-22/5 ans.
Proof:
14/5=-2(-22/5)-6
14/5=44/5-30/5
14/5=14/5

SOLUTION: How can you solve these two equations by substitution? x - 2y = -10 y = -2x - 6