SOLUTION: solve the following system of equations. x-2y=5 -3x+2y=7

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Question 41173: solve the following system of equations.
x-2y=5
-3x+2y=7
Answer by PaulAllen65270(19) About Me  (Show Source):
You can put this solution on YOUR website!
First thing you need to do is get both equations equal to the same thing such as x
x-2y=5
x=2y%2B5
Now for the other equation
-3x%2B2y=7 add 3x to both sides so you will not divide by a negitive
2y=3x%2B7 subtract 7 from both sides
3x=2y-7 divide both sides by 3
x=%282y-7%29%2F3
Now that they both equal x they can be set equal to each other because x=x
2y%2B5=%282y-7%29%2F3 Multiply both sides by 3 to get rid of the fraction
%282y%2B5%29%283%29=2y-7
6y%2B15=2y-7 Subtract 15 from both sides
6y=2y-22 Subtract 2y from both sides
4y=-22 Divide by 4
y=-5.5
Now to find x you substitute the Y you just found in either of the 2 equations
x-2y=5 substitute -5.5 for y
x-2%28-5.5%29=5
x%2B11=5 Subtract 11 from both sides
x=-6
So your answer is
x=-6 & y=-5.5