# MATH

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I NEED TO SOLVE FOR Y AND X
im getting rele confused on this. ok here is the prob.

x+y=5
x-2y=-4

equation 1 x+y=5
equation 2 x-2y=-4

Multiply equation 1 by -1.
Add equation 1 to equation 2. The x term cancels. Solve for y.

THEN, put the value of y into either equation and solve for x.

Finally, put the value of x and y into the OTHER equation and see if those values satisfy the equation.

• MATH -

Multiplying Equation 1 by -1 you get:

-x-y=-5

Adding that to equation 2 you get:

-x -y = -5
+ x -2y = -4
-------------------
-3y = -9
Divide both sides by -3 and you get
y=3
Put that back into either equation and you can solve for x
x+y=5
x+3=5
x+3-3=5-3
x=2
So x=2, y=3 should be the solutions.
Check this in the other equation, x-2y=-4
2-2(3) = -4
2-6 = -4 why yes it does! :-)

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