Question

find the zeros of the polynomial x square - 2 x minus-8

Answer 1

Answer:

$\text{The solution is }x=4,-2$

Step-by-step explanation:

Given the equation

$x^2-2x-8=0$

we have to find the roots of the given equation.

Comparing given equation with standard form of equation

$ax^2+bx+c=0$

$a=1, b=-2, c=-8$

By determinant formula

The solution is

$x^2-2x-8=0\\\\x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\\\\x=\frac{-(-2)\pm\sqrt{(-2)^2-4(1)(-8)}}{2(1)}\\\\x=\frac{-(-2)\pm\sqrt{4+32}}{2}\\\\x=\frac{-(-2)\pm\sqrt{36}}{2}\\\\x=\frac{2\pm6}{2}\\\\x=4,-2$

Answer 2

Answer:

-8 &-2 can be written as -4/x&2/x.

so these are the factors.

x-4=0

x=4

x+2=0

x=-2