PLEASE HELP WILL MARK BRAINLIEST! Also please explain the answer

Answer:
Each triangle is a right triangle.
Step-by-step explanation:
You can see each one has one 90 degree corner.
Answer:
13. True
14. True
15. False
Step-by-step explanation:
By using the Pythagorean Theorem a^2+b^2=c^2, you can evaluate whether or not the triangles are right triangles.
13. 8^2+15^2=17^2 -> 64+225=289 -> TRUE
14. 50^2+120^2=130^2 -> 2500+14400=16900 -> TRUE
15. 12^2+35^2=36^2 -> 144+1225 =/=1296 -> FALSE