Arectangle is 12 feet long and 5 feet wide. if the length of the rectangle is increased by 25% and the width is decreased by 20%, what is the change in the area of the rectangle?

the change in the area of the rectangle square feet.

There was no change in the rectangle's area 

Let's start out by finding what a  increase in the length  is.  or  of  is . Since the length was increased by that much, you add the  to  to get a longer length of 

The same goes for the width:  or  of  is  However, since the width was decreased, we'll subtract this value from , for a shorter width of 

We've found that the new rectangle is  long and  wide. Its area, which is its length  width, is  or 

To find how much the area changed, simply subtract this value from the original area of the rectangle 



We've now found that there was (surprisingly) no change in the rectangle's area, despite changing its size.