Question

if 3x+4y=11 and xy=12 then find the value of 27x3-64y3

Answer 1

Answer:

1331 - 108x²y - 144xy²

Step-by-step explanation:

3x + 4y = 11

Cubing on both sides,

(3x + 4y)³ = 11³

(a+b)³= a³ + 3a²b + 3ab² + b³

Here, a = 3x and b = 4y

(3x + 4y)³ = (3x)³ + (3 * 3x * 3x * 4y) + (3 * 3x * 4y * 4y) + (4y)³

      11³     = 27x³ + 108x²y + 144xy² + 64y³

      1331  = 27x³ + 108x²y + 144xy² + 64y³

27x³ + 64y³ = 1331 - 108x²y - 144xy²

Answer 2

Answer:

Step-by-step explanation: