If x, y are two positive real number and  $$x^{1/3}=y^{1/4}$$, then which of the following relations is true?

If a²+b²+c² = 2(a – b – c) – 3 then the value of 4a – 3b + 5c is 

If x²+y²-4x-4y+8=0, then the value of x-y is: 

If x – y + z = 15, xyz = -216 and xz – xy – yz = 18, then the value of $$ {x^3}-{y^3}+{z^3}=$$

If $$ {8x\over{2x^{2}+7x-2}}=1, x>0,$$ then what is the value of of $$ {x^{3}+{1\over x^{3}}}$$ ?

If 0.4 m + 0.8 n = 2.2 and 0.8 m + 0.4 n = 1.4, then the value of $$ {m^2}+{n^2}$$ is equal to 

Find the value of. 67²–33².

If $$ {x=a^{2\over3}-a^{-2\over3}}$$ then the value of $$ {x^{3}+3x}$$.