Respuesta :
Factorise the equation first of all.
The easiest way to do this is to find two number that add to make the middle (-8) and multiply to make the last number (-9)
Two numbers with this property are -9 and 1
So when you factorise, your equation becomes (x-9)(x+1) = 0
From these you can conclude that for the equation to be equal to 0, either
x-9= 0
So x = 9
Or
x+1 = 0
And
x= -1
The easiest way to do this is to find two number that add to make the middle (-8) and multiply to make the last number (-9)
Two numbers with this property are -9 and 1
So when you factorise, your equation becomes (x-9)(x+1) = 0
From these you can conclude that for the equation to be equal to 0, either
x-9= 0
So x = 9
Or
x+1 = 0
And
x= -1
Answer:
(x+1)(x-9)
Step-by-step explanation:
Break the equation: x²- 8x-9=0 into groups:
([tex]x^{2}[/tex]+x)+(-9x-9)
Factor X out of [tex]x^{2}[/tex]+x: x(x+1)
Then Facor -9 out of (-9x-9): -9(x-1)
This means that you can simplify these 2 equations: (x-9) & (x+1)
So your answer is: (x+1)(x-9)