Nicholas's Burgers cooks its burgers either well done or medium. Last night the restaurant served 65 burgers in all, 13 of which were well done. What percentage of the burgers were well done?

Explanation is in the file

cutt.ly/tz3yDpb

center (1,3) with radius 6

step-by-step explanation:

we must complete the square to find the center and radius of the circle.

first make sure the x and y squared terms have 1 as their coefficients. we also make sure x and y terms together.

we now create space between the x and y terms with parenthesis.

we complete the square by taking the middle terms -2x and the -6y - divide each and square them.

we add the squares to both sides.

simplify.

and write the quadratics in factored form.

the center is (h,k) or (1,3). the radius is the square root of 36 which is 6.