Question

. If x = 2/3 and x = -3 are roots of the quadratic equation ax² + 7x + b = 0 find the value of a and b.

Answer 1

Answer

A = 3 and B = -6

Solution

The equation given = ax^2 + 7x + b = 0

Roots are given x1 = 2/3 and x2 = -3

sum of the roots = x1 + x2 = -b / a

=> 2 / 3 - 3 = -7 / a

=> -7 / 3 = -7 / a

=> a = 3

products of roots = c / a

=> 2 / 3 x (-3) = b / a

=> -2 = b / 3

=> b = -6

therefore, a = 3 and b = -6