If the roots of a quadratic equation are 20 and -7, then find the equation?  Select the correct option:
A) x2 - x - 15 = 0
B) x2 - 12x - 50 = 0
C) x2 - 13x - 140 = 0
D) x2 - 4x - 40 = 0
E) x2 - 23x - 150 = 0
Explanation:   Any quadratic equation is of the form   x2 - (sum of the roots)x + (product of the roots) = 0 ---- (1)   where x is a real variable. As sum of the roots is 13 and product of the roots is -140, the quadratic equation with roots as 20 and -7 is: x2 - 13x - 140 = 0.   Answer x2 - 13x - 140 = 0
<result>C</result>
If the roots of a quadratic equation are 20 and -7, then find the equation?