If X+Y+Z=15 and 1/x+1/y+1/z=0, then what is X^2+Y^2+Z^2?

1X+1Y+1X=0

X+Y+Z=15

What is X2+Y2+Z2?

1 Answer
Apr 29, 2017

X2+Y2+Z2=225

Explanation:

1X+1Y+1Z=0orYZ+ZX+XYXYZ=0or(YZ+ZX+XY)=0

(X+Y+Z)2=X2+Y2+Z2+2(XY+YZ+ZX) or
152=X2+Y2+Z2+20 or
X2+Y2+Z2=225 [Ans]