Find the quadratic equation, whose roots are 5 and -4 and leading coefficient is 3?

1 Answer
Apr 1, 2017

3x^2-3x-60=0

Explanation:

A quadratic equation whose roots are alpha and beta and leading coefficient is a is

a(x-alpha)(x-beta)=0

Hence, the quadratic equation whose roots are 5 and -4 and leading coefficient is 3 is

3(x-5)(x-(-4))=0

or 3(x-5)(x+4)=0

or 3(x^2-5x+4x-20)=0

or 3(x^2-x-20)=0

or 3x^2-3x-60=0