Respuesta :

mh56

Answer:

7

Step-by-step explanation:

I hope this helps

mathstudent55

Answer:

7

Step-by-step explanation:

Pine Street in x miles long.

Maple street is 3 times as long as Pine Street, so Maple street is 3x miles long.

Maple street is 21 miles long.

3x = 21

x = 7

Maple Street is 7 miles long.