The bottom square portion would be 10 x 10 = 100 square inches.
The area of the triangle would be 1/2 x base x height.
The base is 10 - 6 = 4 inches.
The height is 16 -10 = 6 inches.
Area = 1/2 x 4 x 6 = 12 square inches.
Total area = 100 + 12 = 112 square inches.
If you can rewrite the formula as (x-a)² + (y-b)² = r², the center is at (a,b) and the radius is r.
If you work out this equation, and map it to the original, you will find that the +4x term hints that a = 2 (double product) and -12y hints that b=-6, and r=6.
So, the formula can be written as (x+2)² + (y-6)² = 6² and the center is at (-2,6) and the radius is 6.