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If 64x³ - 343y³ = (4x - Ay) X (Bx² + 49y² + Cxy), then find the value of 3 X (2A + 6B) - 2C.

If a + b + c = 8, a² + b² + c² = 18 and ab + b c+ ca = 12, then what is the value of a³ + b³ +c³ –3abc?

If     = 4 then

(a + 7)² + (b – 2) ² + (c + 3) ² = 0, then find the value of 3a - 2b + c.

Two positive numbers differ by 2, and the sum of their reciprocals is 3/4. What is the larger number?

(x + 1)² + (y – 3) ² + (z + 5) ² = 0, then find the value of 2x + 3y - z.

If x + 1/x = 5, then x² + 1/x² is:

(x – 6) ² + (y + 2) ² + (z – 4) ² = 0, then find the value of 4x - 3y + z.

22% of ‘x’ is equal to 66% of ‘y’, then find the value of x: y.