Jessica rewrites expression 1 as d + d + d + 5 + 5 + 5.
why might she have done this?

she wrote it to make it simpler to add.

Step by step:

A triangle has 3 sides. It's given sides are d+5. All sides are d+5 because it is an equilateral triangle.

The answer to the question you were looking for is: SHE COMBINED THE LIKE TERMS SO IT WOULD BE EASY TO ADD THEM.

Hope it helps

step- i d k and i d c : )

you: : 0

bye

54 km / hours

step-by-step explanation:

we need to convert seconds to hours

60 seconds = 1 minutes

60 minutes = 1hour

15 m         60 second   60 minutes

  * *         = 54000 meters/ hour

second     1 minute             1 hour

now we need to convert meters to km

1000 m = 1 km

54000 m       1 km

*   = 54 km / hours

hour               1000m