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Dooga Blackrazor
Oct14-04, 02:43 PM
1. If x^2 + y^2 = 16 and xy = 8 then what is (x+y)^2 ?

32, correct?

90?
120?
1260?
150?

arildno
Oct14-04, 02:48 PM
1. Incorrect; think again.

Dooga Blackrazor
Oct14-04, 02:49 PM
I meant to put 32, whoops.

arildno
Oct14-04, 02:50 PM
Still incorrect..

Dooga Blackrazor
Oct14-04, 02:52 PM
(x+y)^2 = x^2 +2xy + y^2

xy = 8
x^2 + y^2 = 16

2(8) = 16 + 16 = 32

Where am I going wrong?

arildno
Oct14-04, 02:54 PM
Well, from your first post, it says xy=18..

Dooga Blackrazor
Oct14-04, 02:56 PM
Ah, thanks.