Answer:
56.52
Step-by-step explanation:
c=2
r
C=2*3.14*9
C=56.52
Okay so first you want to simplify the given equation (7x+3y)(7x-3y)
in order to do this you multiply the first number of the first equation (7x) with the first number of the second equation (7x) this gives you 49x^2
Now you want to multiply the second number of the first equation (3y) by the second number of the second equation (-3y) this gives you -9y^2
Its as easy as pie!
The answer is 8 because it is the GCF (That means it is the greatest common factor)
HOPE THIS HELPS!!!!!!! ;-)