We can factor this to solve it if it will factor. We can try a few options to see if they work
we know that x times x is x^2 so let's start with that
(x )(x )
We need to get an 8 on the end so we need 2 numbers that multiply to equal 8. The options are 8 and 1 or 2 and 4
Let's try 2 and 4. We also know that all of the signs are positive because there are no negatives in the problem.
(x+2)(x+4)=0
if we distribute that we get x times x is x^2
x times 4 is +4x
2 times x is +2x
2 times 4 is +8
combine all of these and you get
x^2+6x+8
so those are the correct factors
to find the roots we need to set each factor equal to 0 and solve for x
x+2=0
x+4=0
x=-2
x=-4
If you look at the graph you can see that the roots are where the parabola crosses the x axis.
