Question 1064480
Let w be the width of the rectangle. Then the length would be 3w. Now let a be the area of the original rectangle. Then the area of the new rectangle would be n+156. So:
w(3w)=n
3w²=n and
(w+6)(3w+6)=n+156
3w²+24w+36=n+156
24w=120
w=5
The original width of the rectangle was 5 units, and the old length was 15 units. ☺☺☺☺