Question

factorise x square plus 6 x + 8

Answer 1

x²+6x+8

x²+2x+4x+8

x(x+2)+4(x+2)

(x+2)(x+4)

hope it helps

Answer 2

ANSWER

Given =>

Quadratic equation is x^2+6x+8

1)Now we will solve the equation by using the quadratic formula methord.

Here d =b^2 - 4 ×a×c

=>d = (6)^2 - 4×(1)×(8)

=>d = 36 - 32

=>d = 4.

Hence the value of discriminant is 4.

Now according to the quadratic formula we have =>

x = $\dfrac{-b\pm\sqrt d}{2\times a}$

=>x = $\dfrac{-6 \pm\sqrt 4}{2\times 1}$

=>x = $\dfrac{-6 \pm 2}{2}$

So, either x = $\dfrac{-6 - 2}{2}$

=>x = - 4.

Or. x = $\dfrac{-6 + 2}{2}$

=>x = - 2.

So the zeroes of the polynomial is - 2 and - 4.

And the factors are x +4 and x +2.

2)Now we will use the factorisation method to solve it.

x^2+6x+8

=> x^2 +4x + 2x + 8

=> x(x+4) +2(x+4)

=>(x+4)(x+2)

Hence the factors of the polynomial are (x+4) and (x+2).

REMEMBER

In quadratic formula

X = $\dfrac{-b\pm\sqrt{d}}{2\times{a}}$

and

d is discriminant which determines the nature of roots