Question

Without solving the equation, determine the nature of the roots of x^2 - 2x - 8 = 0.

Answer 1

Answer:

two real, unequal  roots

Step-by-step explanation:

This is a quadratic equation.  The quadratic formula can be used to determine how many and what kind of roots may exist:  

Find the discriminant, which is defined as b^2 - 4ac, if ax^2 + bx + c = 0.  In this case, a = 1, b = -2 and c  = -8, so that the discriminant value is

(-2)^2 - 4(1)(-8), or 4 + 32  =  36.

Because the discriminant is real and positive, we know for certain that we have two real, unequal  roots