If a and b are integers such that a - b = 10, find the minimum value of a*b.
a = 5 b = -5 ab = -25
a-b =10 then a = 10 + b
Find the minimum of (10+b)(b) = b^2 + 10 b parabola with min occurs at b = - 10/(2*1) = -5
with b = -5 a = 5
+37153 
