Atriangle has side lengths of 15, 20, and 25. what type of triangle is it?

 Its a RIGHT ANGLED TRIANGLE. 

GIVEN: 
hypo=25 
opposite and adjacent=15 and 20. 

FORMULA: 
hypotenuse^2 =opposite side^2 + adjacent side^2 
25^2=15^2+20^2 
625=225+400 
400+225=625 

so its a right angled triangle 

understand??

25^2 = 20^2 + 15^2
625 = 400 + 225
625 = 625

It's a right triangle.