Yes it is. Input the numbers into the pythagorean theorem,

and if they equal each other it is a right triangle.
Answer:
option A is the correct answer
Answer: 5k +7
Step-by-step explanation: -2k + -7k + 5k is -4K and 2+3=5 -4K +5 and 6k +3k= 9k + 2 then u do -4K plus 9k and get 5k next, 5+2