Two cars leave from the same place at the same time travelin

Two cars leave from the same place at the same time, traveling in opposite directions. One travels 5 kilometers per hour faster than the other. After 3 hours they are 495 kilometers apart. How fast is each car traveling?

Solution

495/3=165 KPH IS THE TOTAL SPEED OF THE TWO CARS.
3X+3(X+5)=495
6X+15=495
6X=495-15
6X=480
X=480/6
X=80 KPH IS THE SPEED OF THE SLOWER CAR.
80+5=85 KPH FOR THE FASTER CAR.
PROOF:
80+85=165
3*80+3*85=495
240+255=495
495=495