If x + y = 3, then what is the value of x 3 + y 3 + 9xy? X+y=3 Wh

If x + y = 3, then what is the value of x 3 + y 3 + 9xy? X+y=3 Wh
| If x + y = 3, then what is the value of x3 + y3 + 9xy?

A. 15

B. 81

C. 27

D. 9

Please scroll down to see the correct answer and solution guide.

Right Answer is: C

SOLUTION

X+y=3
Whole cube on both side
X3 +y3+3xy(x+y)=27
X3 +y3 +3xy(3)=27
X3 +y3 +9xy=27