Find the radius of the circle given by x^2-10x+y^2+8y=18
Put it into standard form of (x-h)^2 + (y-k)^2 = r^2
complete the square for x and y
(x-5)^2 + (y+4)^2 = 18 +25 + 16
(x-5)^2 + (y+4)^2 = 59 soooooo: 59 = r^2 find 'r'
+36916 
