Answer:
i think that this is the answer
Step-by-step explanation:
10x5=50
x^2 + y^2 - 4y - 15 = 6
x^2 + y^2 - 4y = 21
x^2 + y^2 - 4y + 4 = 25
x^2 + (y - 2)^2 = 5^2
r = 5