Between 4 and 6 is where u put the grouping symbols!
I think you just divide the number of miles by the number of hours he spent driving.
2,482/42.5= 58.4
58mph
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:

Answer:
7.2*10^3.
7,200 in scientific notation, is 7.2*10^3