Answer: 
Step-by-step explanation:
By the Pythagorean theorem, the unknown side has length

Therefore,

Answer:
who is that? Maybe i know this person...
Step-by-step explanation:
Answer:
(x-5)² + y² = 4
Step-by-step explanation:
formula of circle: (x-h)² + (y-k)² = r² where (h,k) is coordinate of center and r is radius
center: (5 , 0) r = 2
Equation: (x-5)² + y² = 4