Question

Can someone explain this to me? I already know the answer, but I don't understand why its the answer.

Without solving the equation, determine the nature of the roots of x2 - 2x - 8 = 0.


Two, real unequal roots
Two, real equal roots
No real roots

Answer 1

\[ax^2+bx+c=0\]consider the discriminant
\[\Delta=b^2-4ac\]

Answer 2

the discriminant is part of the quadratic formula
\[x=\frac{-b\pm\sqrt{\Delta}}{2a}\]

Answer 3

the quadratic formula takes plus and minus the square root of the discriminant,

plus and minus a square root will have one value if the term in the square root is 0,

two values if the term in the sqrt is positive,

and no real values f the term in the square is negative

Answer 4

*if

Answer 5

Okay thanks, this is a mouthful but I understand lol.

Answer 6

**and no real values if the term in the square root is negative

Answer 7

yeah it is a complicate formula