Answer:
c = x + 5
Step-by-step explanation:
using Pythagoras' identity in the right triangle
c² = 5² + ([tex]\sqrt{x^2+10x}[/tex] )²
= 25 + x² + 10x
= x² + 10x + 25 ← a perfect square
c² = (x + 5)²
take the square root of both sides
c = [tex]\sqrt{(x+5)^2}[/tex] = x + 5
