Answer:
y=3/4 x+1
Step-by-step explanation:
first you start with y=mx+b find the y intercept first which is 1 next you just count down the block which is 3 then count to the right till you find a spot where it lands which would get you y=3/4+1
The formula for Average speed = 
The car travels 80 km in 1 hour.
Then the car travels 90 km in 2 hours.
And finally the car travels 76 km in 1 hour
So the total distance covered by the car = 80 + 90 + 76 = 246 km
The total time taken to cover this distance = 1 + 2 + 1 = 4 hours.
So average speed = 
The average speed of the car is 61.5 km / h