SOLUTION: How do you solve by using elimination with 2x-4y=28 4x=17-5y

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Question 776115: How do you solve by using elimination with 2x-4y=28 4x=17-5y
Found 2 solutions by rothauserc, MathTherapy:
Answer by rothauserc(4718) About Me  (Show Source):
You can put this solution on YOUR website!
How do you solve by using elimination with 2x-4y=28 4x=17-5y
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we have two equations in two unknowns
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2x = 4y+28
divide both sides of = by 2
x = 2y +14
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Substitute for x in second equation
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4*(2y+14) = 17 -5y
8y +56 = 17 -5y
13y = -39
y = -3
======================
2x -4*(-3) = 28
2x +12 = 28
2x = 16
x = 8
=========================================
x = 8, y = -3

Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

How do you solve by using elimination with 2x-4y=28 4x=17-5y

2x - 4y = 28 ----- eq (i)

4x + 5y = 17 ----- eq (ii)

It's easiest to multiply eq (i) by - 2, or 2 and then add, or subtract both equations to ELIMINATE the x-variable, and determine the y-value. Then substitute the y-value into any of the 2 equations and determine the value of x.

You could also multiply eq (i) by 5 and eq (ii) by 4 to ELIMINATE the y-variable, but this would entail a little bit more work.