निम्नलिखित प्रश्न

Simplify:
6x + 8y - [(12x + 6y) - (4x + 3y) + 2y] - 4x

If √c + (1/√c) = 7, then find the value of c + (1/c).

If √b + (1/√b) = 11, then find the value of b + (1/b).

If (a – 8) ²  + (b + 2)  ²  + (c – 3) ²  = 0, then find the value √(a +b + c).

If a + b + c + d = 4,  then the value of  

If, ( a + b = 10 ) and ( a² + b² = 58 ), then find the value of (a³ + b³). 

If x + y + z = 20, x² + Y² + z² = 160 and x z = y², then find the value of x z?