Problema Solution

the length of a rectangle is 12 mm less than twice its width. if its length is decreased by 2 mm and its width is increased by 3 mm , the perimeter is 86 mm. what are the dimensions of the new rectangle?

Answer provided by our tutors

Let


l = the length of the rectangle

w = the width of the rectangle

P = 2*(l+w) the perimeter of the rectangle


l = 2*w - 12

2*(l - 2 + w + 3) = 68


We need to find the dimensions of the new rectangle.


The solutions of the system of equations


l = 2*w - 12

2*(l - 2 + w + 3) = 68


are


l = 18 mm

w = 15 mm


Thus the dimensions of the new rectangle are 18 - 2 = 16 mm and 15 + 3 = 18 mm.