If x – y = 5 and xy = 15, then what is the value of $$\text{x}^3-\text{y}^3$$​?

Correct option is A

Given:

x - y = 5

xy = 15

Formula Used:

​$$x^3 - y^3 = (x - y)(x^2 + xy + y^2)$$

$$x^2 + y^2 = (x - y)^2 + 2xy$$​​

Solution:

​$$x^2 + y^2 = 25 + 2 \times 15 = 55$$​​

$$x^3 - y^3 = (x - y)(x^2 + xy + y^2) = 5(55 + 15) = 5 \times 70 = 350$$