The length of a rectangle is three times its breadth

Question

If the area is 48m2 find the perimeter

Answer 1

L is the length of the rectangle

W is the width of the rectangle, or as you can it, it's breadth

 

      Area = length x width = L * W = LW

 

      It is given that the length is three times as long, so L = 3*W = 3W;

      Substituting this into the area equation results in:

 

      48 = Area = LW = (3W)*W = 3*W^2

 

     16 = W^2  <-- divides both sides by 3

 

     Either by factoring difference of squares (W+4)(W-4)=0

     or taking the square root of both sides, the width must

     be 4 because it cannot have a negative value of -4.

 

     So the width, or breadth, W = 4 --->  L = 12

     The area is in fact 48, and its perimeter is P=2*4 + 2*12 = 8 + 24 = 32