Hello,
Let's find the roots of equation "x^2 +5x-6''
We have :
a = 1
b = 5
c = -6
Delta = b^2 - 4ac
Delta = 5^2 - 4.1.(-6)
Delta = 25 + 24
Delta = 49
Then,
x = [ -b +/- √( Delta) ]/2a
Replacing the values:
x = [ -5 +/- √(49) ] /2.1
x = [ -5 +/- 7]/2
Then,
x' = (-5-7)/2 <=> -6
And
x" = (-5+7)/2 <=> 1
As ax^2+bx+c = a(x-x')(x-x")
Then,
x^2 +5x-6 = 1.(x-(-6))(x-1)
= (x+6).(x-1)
Now replacing this equation:
(x^2+5x-6)/(x+6) = (x+6).(x-1) / (x+6)
Cuting, (x+6) we stay with:
= (x+1)
= x+1
I hope this has helped!
