Answer:
No, Yes, Yes, No
Explanation:
The most clear aspect of right triangles is, the sum of square value of two of its legs is equal to square value of hypotenuse (the longest side)
for the first option:
10, 15, 20 : No
10^2+15^2 = 325 while the suare value of 20 is equal to 400.
we don't have to check the following values:
8,15,17 : Yes
5,12,13 : Yes
Because these are the side lengths of special right triangles according to Pythagoras
as for 4,5,6
4^2 + 5^2 = 41 while the square value of 6^2 = 36