SOLUTION: If the difference between two numbers is 6, and the difference of their squares is 180, what is the sum of the numbers?

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Question 907836: If the difference between two numbers is 6, and the difference of their squares is 180, what is the sum of the numbers?

Found 2 solutions by ewatrrr, MathLover1:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
x the smaller number
(x+6)^2 - x^2 = 180
12x + 36 = 180
12x = 144
x = 12, the smaller number. Larger is 18
and..
324-144 = 180

Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

let's numbers be x and y

If the difference between two numbers is 6,we have
x-y=6......eq.1
and if the difference of their squares is 180,
x%5E2-y%5E2=180.............eq.2
you got system to solve:

x-y=6......eq.1
x%5E2-y%5E2=180.............eq.2
_________________________________
x-y=6......eq.1...solve for x
x=y%2B6......substitute in eq.2

%28y%2B6%29%5E2-y%5E2=180 .............eq.2...solve for y
y%5E2%2B12y%2B36-y%5E2=180
cross%28y%5E2%29%2B12y%2B36-cross%28y%5E2%29=180
12y=180-36
12y=144
y=144%2F12
y=12
now find x=y%2B6
x=12%2B6
x=18
check:
x-y=6=>18-12=6=>6=6
x%5E2-y%5E2=180=> 18%5E2-12%5E2=180=>324-144=180=>180=180