SOLUTION: Given that x-y= 8•sqrt(2) and xy= 137, where x and y are both positive, find the value of x+y without finding x or y

Question 1139332: Given that x-y= 8•sqrt(2) and xy= 137, where x and y are both positive, find the value of x+y without finding x or y
Found 2 solutions by ikleyn, greenestamps:
Answer by ikleyn(52778) (Show Source): You can put this solution on YOUR website!
.

The idea is to express (x+y)^2 via given data, and then take square root of this expression (of this number). It will be exactly (x+y). So, = + 4xy = + 4*137 = 64*2 + 4*137 = 676. Therefore, (x+y) = = 26. ANSWER. x + y = 26.

Answered and solved.

Answer by greenestamps(13198) (Show Source): You can put this solution on YOUR website!

Given:
(1)
(2)

Square equation (1):

Add 4 times equation (2):

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