Question 222428
Let x = width
3x= length


2W+2L = P
2(x) + 2(3x)=320
2x+6x= 320
8x = 320
x=320/8= 40  Width
3x= 3*40= 120  Length


Check:

2*40+2*120
80+240
320  It checks!


For additional explanation on Word Problems like this, please see my own website.  Do a "Bing" search for my last name "Rapalje".  Look for "Rapalje Homepage" near the top of the search list.  On my Homepage near the top, look for the link "Basic, Intermediate and College Algebra: One Step at a Time."  Choose "Basic Algebra", and look in Chapter 1 for several topics on Word Problems, especially Section 1.10 Part I that specifically covers perimeter of rectangles like this one.  In these sections, you will find my own non-traditional explanations, that my own students all said were a LOT easier to understand than traditional textbooks.  See also the corresponding "MATH IN LIVING COLOR" pages in which problems are solved IN COLOR!  


R^2


Dr. Robert J. Rapalje, Retired
Seminole State College of Florida
Altamonte Springs Campus