Question

* 1. If 777x + 666 = 999, and 666x + 777y = 444 then x^3 - y^3 is equal to (A) 19 (B) 35 (C)-35 (D)-19​

Answer 1

Step-by-step explanation:

Equations give

7 x + 6y = 9 and

6 x + 7 y =4

=> (36 – 49)y = 54 – 28 = 26

or, y = – 2

or, x = 3

or, x³ – y³ = 35