SOLUTION: a boy is three years older than his sister.the sum of their square ages is 369.how old are they

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Question 714844: a boy is three years older than his sister.the sum of their square ages is 369.how old are they
Found 3 solutions by lynnlo, JAE96, Alan3354:
Answer by lynnlo(4176) About Me  (Show Source):
Answer by JAE96(1) About Me  (Show Source):
You can put this solution on YOUR website!
369= (x+3)+ (x)
369= (2x + 3)
369 - 3 = 2x +3 -3
366/2=2x/2
183 = x (The sister's age)
183+3 = 186(The Brother's age)
Plug it back in...
369 (186)+(183)
369=369

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
a boy is three years older than his sister.the sum of their square ages is 369.how old are they
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x%5E2+%2B+%28x%2B3%29%5E2+=+369
2x%5E2+%2B+6x+-+360+=+0
x%5E2+%2B+3x+-+180+=+0
(x - 15)*(x + 18) = 0
x = 15
--> 15 & 18
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Ignore the negative solution.