Explanation:
We khow the sum and the product of the zeroes of this quadratic polynomial
Here is a trick :
when we khow the sum S and the product P ofvtwo numbers we can find them by solving :
x²-Sx+p=0
here S= -8 and P=12
so:
x²+8x+12=0
Let Δ be the discrminant of this equation: a= 1 , b= 8 and c=12
Δ= 8²-4*12 =16
the zeros are:
(-8-4)/2= -6
(-8+4)/2 = -2
verify:
-6+(-2)= -8
-2*(-6)= 12
now the polynomial quadratic is:
(x+6)(x+2)