Question

If xy = 16 and $x^2+y^2=32$then the value of x+y=?

• A. 10
• B. 4
• C. 8
• D. 6

Answer 1

Answer:

C. 8

$(x+y)^2=x^2+y^2+2xy$

$(x+y)^2=32+2\times16$

$=32+32=64$

$(x+y)=\sqrt{64}=8$