Alvin's Scribepost for December 14, 2009

Question #14

Show whether each triangle in the table is a right triangle.
Triangle Side Lengths
A 9, 12, 15
B 7, 8, 11
C 7, 24, 25
D 16, 30, 34
E 10, 11, 14

Triangle A is a right triangle because 9 squared is 81 and 12 squared is 144, and 15 squared is 225 which then you can make this statement 81 + 144 = 225 ( 9 squared + 12 squared = 15 squared).

Triangle B is not a right triangle because 7 squared is 49 and 8 squared is 64, and 11 squared is 121 which then you can't make an addition statement because 49 + 64 doesn't equal 121 it equals 113.

Triangle C is a right triangle because 7 squared is 49 and 24 squared is 576 , and 15 squared is 625 which then you can make an addition statement because 49 + 576 = 625 ( 7 squared + 24 squared = 25 squared)

Triangle D is a perfect square because 16 squared is 256 and 30 squared is 900, and 34 squared is 1156 which then you can make an addition statement because 256 + 900 = 1156 ( 16 squared + 30 squared = 34 squared)

Triangle E is not a perfect square because 10 squared is 100 and 11 squared is 121, and 14 squared is 196 which cannot make an addition statement because 100 + 121 is clearly 221.

(which I meant addition statement, I really meant Pythagorean theorem)