I assume you are asking to solve:
-2x^2 + 3x - 9 = 0
So first, this equation does not have real roots.
It only has 2 complex roots.
The roots are:
3/4 * (1-i√7) and 3/4 * (1+i√7)
I would use a proportion:
336 miles/7 hours = x miles/15 hours (cross multiply)
x= 720 miles

<h2>33 km</h2>
3.3cm = 0.000033km (divide by 100,000.
So, 0.000033km/yr.
0.000033 × 1,000,000
=33km