Question

A triangle has side lengths 10, 15, and 7. Is the triangle a cute, obtuse, or right ? Show your work and explain.

Answer 1

hey try tagging people

Answer 2

What do you mean?

Answer 3

we have a triangle with sides a,b,c

a = 10
b = 7
c = 15

make 'c' the longest side. The 'a' and 'b' can be in either order. It doesn't matter

now tell me what a^2+b^2 = 10^2+7^2 is equal to

Answer 4

149

Answer 5

correct

Answer 6

what is c^2 = 15^2 equal to?

Answer 7

225

Answer 8

correct

Answer 9

now compare the two results

a^2+b^2 = 149
c^2 = 225

we see that the `c^2` expression is larger, so \(\Large c^2 > a^2+b^2\) . Based on these rules here

http://images.slideplayer.com/8/2473263/slides/slide_4.jpg

this means that we have an obtuse triangle