Well since the formula is A squared plus B squared = C squared you plug in the 9 for A squared and the 12 for C squared so it looks like 9 + B squared = 12 then you take 9 squared and 12 squared 9 squared = 81 while 12 squared = 144. Then you set up a equation. 81(9 squared) + b squared= 144(12 squared). Now you subtract 144 - 81 = 63. So your equation becomes 81 + 63 = 144 Since your solving for B and not B squared you must find the square root of 63 which is 7.9. Your final answer is 7.9 or the other side of your triangle is 7.9. Hope I helped!
