I don’t understand stand this can somebody please help me

C

Step-by-step explanation:

The radius is 7, but in the standard form for a circle, the radius is squared which means that the answer is NOT A and B.

So now you have only two choices, C and D both of which have the radius shown as 49 which is 7 squared.

The center is at (5,-1)

that means that x will be written as (x - 5)

And y will be written as (y + 1)

Note: the signs of the center always change to the opposite of what they were.

The answer is (x - 5)^2 + (y  + 1)^2 = 49