 Quandaries and Queries Hello, My daughhter, who is a 9th grader is attempting to cut a piece of wood after determining the length of the cut for the hypotenuse.  These are the measures: a=4squared, b=6squared.  She determined that c should equal 52.  But when she measured the actual piece to be cut, c measured 39.5 inches!  Can you offer any insight as to what she is doing wrong?  I have suggested that she may be working with an Acute rather than a Right angle .  But she insists that it is a Right angle after using a "framing square".  Thank you in advance, Florita Hi Florita, So, a = 16, b = 36, these are the two sides of the triangle, and your daughter simply added them to get 16 + 36 = 52. The formula for the hypothenuse of a right triangle is the square root of the squares of the sides, which in this case is sqrt(162 + 362) = sqrt(256 + 1296) = sqrt(1552) = about 39.4. Your daughter may have tried to do this but did the following mistake: sqrt(256 + 1296) = sqrt(256) + sqrt(1296) = 16 + 36 = 52. Indeed the square root of a sum is not equal to the sum of square roots of the terms, so it is important to perform the addition before taking the square root. Claude Go to Math Central