SOLUTION: x+y=5 and xy=4 find x-y?

Question 667831: x+y=5 and xy=4 find x-y?
Found 2 solutions by swincher4391, Alan3354:
Answer by swincher4391(1107) (Show Source): You can put this solution on YOUR website!
x+y =5 and xy=4
y = 5-x and plug into xy=4 to get:
x(5-x) = 4
5x - x^2 = 4
x^2 -5x +4 = 0
(x-1)(x-4) = 0
x = 1 and x = 4
When x =1, y = 4
When x =4, y =1
So in case 1: x-y = 1-4 = -3
Case 2: x-y = 4-1 = 3
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
x+y=5 and xy=4 find x-y?
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x*(5-x) = 4

x = 1, y = 4 --> x-y = -3
x = 4, y = 1 --> x-y = 3

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