SOLUTION: One number is 4 more than another. The difference between their squares is 80. What are the number?

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Question 593629: One number is 4 more than another. The difference between their squares is 80.
What are the number?
Answer by Maths68(1474) About Me  (Show Source):
You can put this solution on YOUR website!
Let
numbers are x and y
one number is 4 more than another
x=y%2B4...........(1)
The difference between their squares is 80
x%5E2-y%5E2=80..........(2)
put the value of x from (1) to (2)
%28y%2B4%29%5E2-y%5E2=80
y%5E2%2B8y%2B16-y%5E2=80
cross%28y%5E2%29%2B8y%2B16-cross%28y%5E2%29=80
8y%2B16=80
8y=80-16
8y=64
8y%2F8=64%2F8
cross%288%29y%2Fcross%288%29=cross%2864%29%2Fcross%288%29
y=8
Put the value of y in (1)
x=y%2B4...........(1)
x=8%2B4
x=12
Numbers are 12,8