The circle passes through the point (3,6). . What is its radius?

We write the mathematical expression correctly:   1/2 + (2/5) s = s - 3/4  we group similar terms:   s (1- (2/5)) = 1/2 - 3/4  we rewrite:   s (5 / 5- (2/5)) = 2/4 - 3/4  s (3/5) = -1/4  s = (5/3) * (- 1/4)  s = -5 / 12  answer:   the value of s is:   s = -5 / 12