If the car can travel 81 km in one hour, (60 minutes) that means that it can travel 81/60 in a minute. The result is 1.35, and this times 15 will give you the amount the car can travel in 15 minutes. The answer is 20.25km
X is 0, so it cancels out the 7. So then 3 divided by 30 is 10. Y=10.
Hmm I use to know this wait a second I’ll answer it
Since y is 5.2 you can substitute it in your equations 5.2 = -5x - 40 then you do things like normal add 40 in both sides and divide -5 in both sides you get 9.04