Question

Given (3m + n)2 = 100 and (3m - n)2 = 4
What is the value of mn?

Answer 1

Answer:

(3m+n)2=100

6m+2n=100

6m+n=100/2

6m+n=50

(3m-n)2=4

6m-2n=4

6m-n=4/2

6m-n=2