Even when Poland was under the control of the former Soviet Union, the A. Catholic Church unified the people

B. Polish people developed vital minerals

C. Communists unified the people

D. Polish people developed industry​

the answer would be the third option, "no, ariel should have added 9^2 and 12^2 and compared that to 15^2."

this is found through the pythagorean theorem, which is a^2 + b^2 = c^2.

this is the correct way of solving the problem:

9^2 + 12^2 = 15^2

81 + 144 = 225

225 = 225