SOLUTION: The tens digit of a certain number is 7 less than the units digit. The sum of the squares of the two digits is 85. Find the number

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Question 344807: The tens digit of a certain number is 7 less than the units digit. The sum of the squares of the two digits is 85. Find the number
Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
y-x=7 y=x+7
x^2+y^2=85
x^2+(x+7)^2=85
x^2+x^2+14x+49-85=0
2x^2+14x-36=0
(2x+18)(x-2)=0
x-2=0
x=2
y=2+7=9
92 is the answer.
Proof:
9^2+2*2=85
81+4=85
85=85