You can determine the actual markdown by changing the percentage to a decimal then multiplying it by the price to find your mark down.
Answer:
(x+9)^2+(y+5)^2=81
Step-by-step explanation:
(x-h)^2+(y-k)^2=r^2
(h,k)=center
r=radius
so if you just insert the center (-9,-5) and the r with 9
(x-(-9))^2+(y-(-5))^2=9^2
(x+9)^2+(y+5)^2=81
Hope that helps :)
Add all the numbers of the triangle and then divide them by the sides