 Welcome geometry students. We're going to work on the converse of the Pythagorean theorem again in this video So have your paper and pencil ready follow along and we're going to work through two steps First of all, we're going to solve question a is it a triangle? So to solve that we are just going to verify that it's a triangle by adding the two smaller sides Five plus six and if that is greater than the third side, we have a triangle and 11 is greater than seven So yes, we have a triangle and now we can try to classify it So now for part B We're going to go back and look at our numbers five six and seven and we're going to put them in order So that we are doing the Pythagorean theorems converse So we're going to look at C squared and compare it to a squared plus B squared C has to be the hypotenuse the longest side so it is a 7 so we're going to compare 7 squared or 49 To 5 squared plus 6 squared They're called the legs if 5 and 6 are interchangeable. It doesn't matter which one is substituted for a or B So we do our calculations and we have 49. We want to compare it to 25 plus 36 25 plus 36 is 61 so 49 is less than 61 and therefore we have an acute Triangle and you've worked with the Pythagorean theorems converse