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

Mathematics

1 answer:

noname [10]3 years ago

3 0

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

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