Respuesta :

Hi there!

Let's use the pythagorean theorem for both sets of values.

WORK:
[tex] {15}^{2} + {18}^{2} = {20}^{2} [/tex]
[tex]225 + 324 = 400[/tex]
[tex]549 > 400[/tex]
The first set of values is an ACUTE triangle.

[tex] {7}^{2} + {8}^{2} = {11}^{2} [/tex]
[tex]49 + 64 = 121[/tex]
[tex]113 < 121[/tex]
The second set of values is an OBTUSE triangle.

Hope this helps!! :)