Two rectangular gardens have the same width of 10 feet the length of one is 20 feet the total area is 500 feet what is the length of the other garden

A = l x w
= 10 x 20
= 200 

this is the area of the first rectangle. now that you know the area, you can subtract it from 500 to then solve the length of the other rectangle.

A = l x w
500-200 = l x 10
300 = l x 10
300/10 = l
30 = l

therefore the length of the second rectangle is 30 feet.

hope this helps! Let me know if you did not understand a step or concept!