somebody please help me ive been trying for hours

Answer:
width = 5k^2
length( 3k^2 +7k +4)
Step-by-step explanation:
15k^4 +35k^3 +20k^2
The width is the greatest common factor
We can factor 5k^2 out
5k^2( 3k^2 +7k +4)
The length is what is inside the parentheses