SOLUTION: Two numbers differ by 8 their product is 65.find the number

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Question 1198032: Two numbers differ by 8 their product is 65.find the number
Found 2 solutions by ewatrrr, MathLover1:
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
Two numbers differ by 8 their product is 65.
find the number:
x(x-8) = 65
x^2 - 8x - 65 = 0
(x + 5)(x - 13) = 0
x = -5 0r x = 13
checking:
-5(-13) = 65
13(5) = 65 checks

Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!

let two numbers be x and y
if two numbers differ by 8 we have

x-y=8............solve for x
x=8%2By..........eq.1

if their product is 65 we have
xy=65........sustitute x

%288%2By%29y=65
8y%2By%5E2=65
y%5E2%2B8y-65=0......factor
%28y+-+5%29%28y+%2B+13%29+=+0
solutions:
%28y+-+5%29=+0->y=5
%28y+%2B+13%29+=+0->y=-13

then
x=8%2By->x=8%2B5->x=13
x=8%2By->x=8-13->x=-5


the numbers are:
x=13,y=5
or
x=-5,y=-13