Question

Evaluate when x=3 and y=-5
(2x)^3+y^3

My figuring:
2*3=6, 6*6*6=216
(-5)(-5)(-5)=-125

Solution: 91

According to my teacher, the answer should be -7, not 91. Who is right, and why?

Answer 1

(2x)^3+y^3
= (6)^3 + (-5)^3
= 216 + (-125)
= 91

If you typed the question correctly, and those are the values of x and y, then 91 is the correct answer.

Answer 2

Ok thank you