SOLUTION: How to solve for x and y? X+Y=30 and X*Y=209

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Question 392860: How to solve for x and y?
X+Y=30 and X*Y=209
Answer by checkley79(3341) About Me  (Show Source):
You can put this solution on YOUR website!
X+Y=30
X=30-Y
X*Y=209
REPLACE X WITH 30-Y IN THE SECOND EQUATION & SOLVE FOR Y.
(30-Y)Y=209
30Y-Y^2=209
Y^2-30Y+209=0
(Y-19)(Y-11)=0
Y-19=0
Y=19 ANS.
Y-11=0
Y=11 ANS.
PROOF:
19+11=30
30=30
11*19=209
209=209