please help me thank u :)

Answer:
x = 17
Step-by-step explanation:
Pythagorean Theorem: a^2 + b^2 = c^2
15^2 + 8^2 = c^2 (15^2 = 225 and 8^2 = 64)
225 + 64 = 289
[tex]\sqrt{289}[/tex] = 17