You haven't provided the required roots, but I can tell you how to do this kind of exercises in general.
If the 
coefficient is 1, i.e. the equation is written like 
, then you can say the following about the coefficients b and c:
is the opposite of the sum of the roots
is the multiplication of the roots.
So, for example, if we want an equation whose roots are 4 and -2, we have:
So, the equation is 
If your roots are rational, you can work like this: suppose you want an equation with roots 3/4 and 1/2. You have:
And so the equation is
In order to have integer coefficients, you can multiply both sides of the equation by 8:
Ben drinks 3 1/2 liters of tea every 40 minutes.
This means that he would drink 1 3/4 of tea every 20 minutes (divide both sides by 2).
Now, let's multiply each side by 3.
1.75 * 3 = 5.25 (aka 5 1/4)
20 * 3 = 60 minutes (an hour)
He drinks 5 1/4 liters of tea in one hour.
(12,-6) (4,-2)
4/12= 1/3
-2/-6= 1/3
the scale factor is 1/3
(S=D/T)S=216KM, T=8HOURS : 216/8=27KM/HOUR
just divide 20 by coefficient of x
x < 20/2
x < 10
