Question

What is the equation of this circle in standard form?

(x−1)2+(y+1)2=5

(x−1)2+(y+1)2=25

(x+1)2+(y−1)2=25

(x+1)2+(y−1)2=5

Answer 1

I'll assume that all the (x and y) expressions are raised to the 2 power, not x2, as written:

E.g.: (x+1)^2+(y−1)^2=25 not (x+1)2+(y−1)2=25

(x+1)^2+(y−1)^2=25 matches the graph.

Explanation:

The center will be at (-1,1): (x+1)=0 and (y-1) = 0

(x+1)^2+(y−1)^2=25 matches the graph.