Answer:
Step-by-step explanation:
Just so you know, the answer is NOT B, as one person stated.
In order for a right triangle to be a right triangle, 2 things have to happen. One is that it has a hypotenuse, which by definition, is the longest side in a right triangle. To test to see if that hypotenuse is actually a hypotenuse, the square of it has to be equal to the sum of the squares of the other 2 sides. Let's test a first.
Keeping in mind that the longest side has to be the hypotenuse, in a. our hypotenuse would have to be 17. Using Pythagorean's Theorem to test:
[tex]8^2+15^2=17^2[/tex] and
64 + 225 = 289 and
289 = 289. So a is a right triangle. Now for b:
[tex]20^2+21^2=29^2[/tex] and
400 + 441 = 841 and
841 = 841. So b is also a right triangle. Now for c:
[tex]9^2+16^2=18^2[/tex] and
81 + 256 = 324 and
337 = 324. Obviously, 337 does not equal 324, so c is not a right triangle.
