Answer:9
Step-by-step explanation:
4x4=16
16-7=9
You do 80km/1hr = n/3.75
Use this proportion to find that n=300
So, he drives 800km.
Answer:

Step-by-step explanation:
For finding the system of equations you can use one of two methods. There's the elimination method and also the substitution method. For this I think the best way we could go at solving this is by using the elimination method. Since we can eliminate the 2y. We can then solve for x and then we'll go from there.

Now that we know what x is we can substitute it for one of the equations and then we will be able to solve for y.

So now we have the x and the y and once we place them together we can get the solution of those two equations, and the solution is
.