Answer: 21 . . . . . .
Credit to the person below-
use cross products
(3r+6) *2 = 9*(2r-4)
6r+12 = 18r-36 distribute
12 = 12 r -36 subtract 6r from each side
48 = 12r add 36 to each side
4=r divide by 12
The copper wire was 150 meters longer than the steel wire. You take 240-60 and get 180. You can then divide that number by 2 to figure out how long the steel wire was to get 90. From there, subtract the 90 by the original 240 and you’ll get 150.
