Question

What will be the nature of the roots of the quadratic equation x^2 + 10x + 25?

(a) Imaginary

(b) Real

(c) Irrational

(d) Equal

I got this question in a job interview.

Question is from Quadratic Equation in chapter Quadratic Equation of Mathematics – Class 10

Answer 1

Right choice is (d) Equal

Best explanation: To check the nature of the roots, the discriminant must be either equal to zero, less than zero or greater than zero.

Discriminant = b^2 – 4ac = 10^2 – 4 × 25 × 1 = 100 – 100 = 0

Since discriminant is equal to zero, the roots of the equation are equal.