If a=25, b=15 , c=-10 then find the value of $$ {a^{3}+b^{3}+c^{3}-3abc\over {(a-b)^{2}+(b-c)^{2} +(c-a)^{2}}}$$

If 4x² + y² = 40 and xy = 6, then find the value of 2x + y.

If 15x² – 26x + 8 = (Ax + B) (Cx + D), where A and C are positive integers, then what is the value of (2A + B – C – 2D) ?

If $$ {x+{1\over x}=7}$$ then $$ {x^{2}+{1\over {x^{2}}}=?}$$

 If 3x²-5x+1=0, then the value of ( $$x^2+{1\over 9x^2}$$) is 

If $$ {a={1+x\over 2-x}}$$, then find the value $$ {1\over {a+1}}+{2a+1\over{a^{2}-1}}$$ ?

If (x + 6y) = 8, and xy = 2, where x > O, what is the value of (x³+216y³)?

Directions: In each of these questions, two equations (i) and (ii) are given, you have to solve both the equations and give answer accordingly.

(i) 12x² + 11x + 2 = 0
(ii) 12y²+ 7y + 1 = 0