The length of a rectangular piece of land is three times the with the area of the land is 480000m2 find the perimeter of the land

Question

I Am really struggling to work this question out I have been stuck on it for weeks now

Answer 1

I'm sorry you've been struggling. I hope I can help you understand this. Let's call the length of the land, x, and the width of the land, y.

 

We know that the area of a rectangle is the length x width. We can use this based on the information we are given:

Area = x*y= 480,000 m^2, where x is the length and y is the width. Let's call this equation (1).

 

We also know that the length is 3x longer the width. We can express this as:

x = 3*y   Let's call this equation (2)

 

We now have two equations and two unknowns, so we can find solutions to our variables x and y. Plug in equation (2) into equation (1):

 

x*y= (3*y)*y=3*y^2= 480,000

y^2= 480,000/3= 160,000

width= y= Square root of 160,000= 400m 

 

length= x= 3*y= 3*400= 1200m 

 

 

Let's check by multiplying our calculated width by the length to see if we get the same area:

400 m * 1200 m= 480, 000 m^2   so our numbers look good!

 

Hope that helps :)