" 16."(x+y+z)^(2)=?

If the real numbers x, y, z are such that x^2 + 4y^2 + 16z^2 = 48 and xy + 4yz + 2zx = 24 . what is the value of x^(2) +y^(2) z^(2) =?

If (x-3)^(2) + (y-5)^(2) + (z-4)^(2) = 0, then the value of (x^2)/(9) + (y^2)/(25) + (z^2)/(16) is

Factories 25 x ^(2) + 16 y ^(2) + 4z ^(2) - 40 xy + 16 xy - 20xy

Multiply each of the monomial : 3/4x^2y z^2,\ 0. 5 x y^2z^2,\ 1. 16 x^2y z^3,\ 2x y z

If a^2+b^2+c^2 =16, x^2+y^2+z^2 = 25 and ax+by+cz = 20 , then show that (a+b+c) prop (x+y+z)