Find the roots of each of the following equations, if they exist, by applying the quadratic formula:

2x2 + x – 4 = 0

Given: 2x2 + x – 4 = 0

Comparing with standard quadratic equation ax2 + bx + c = 0


a = 2, b = 1, c = – 4


Discriminant D = b2 – 4ac


= (1)2 – 4.2. – 4


= 1 + 32 = 33 > 0


Hence the roots of equation are real.


Roots are given by





Hence the roots of equation are


4