Question

the length of rectangle 3cm more than its width its area is 470cm find the width

Answer 1

the length is x
the width (since it is 3 cm longer than the length) is x+3

The formula for the Area of a rectangle is
\(\LARGE\color{blue}{ A_{\rm rectangle}=\rm{length} \times \rm{width} }\)

And we are also given that the area is 470cm.

So let's fill everything in....

\(\LARGE\color{blue}{ 470=\rm{x} \times \rm{(x+3)} }\)

Answer 2

from here you should be able to go on your own.