Provide an example of two trinomials whose sum is 12x^3+13x

Shelly's average speed is 5.25 miles per hour.

It take 8 hours to travel 42 miles.

Step-by-step explanation:

Given : Shelly biked 21 miles in 4 hours

To Calculate :

Shelly's average speed in miles per hour.

At that same rate how many hours will it take Shelly to bike 42 miles?

Solution :

We know that shelly traveled distance = 21 miles

She covered 21 miles in hours = 4

Now to calculate her speed we will use formula :

So, Shelly's average speed is 5.25 miles per hour.

Now she traveled 42 miles with same speed (5.25 miles per hour)

Now time taken to cover 42 miles :

Hence it take 8 hours to travel 42 miles.