text: # The length of the rectangle is 2 times its width, what is the width of the rectangle if the perimeter is 126 cm
  
  The length of the rectangle is 2 times its width, what is the width of the rectangle if the perimeter is 126 cm, make an equation according to the condition of the problem, taking the width of the rectangle for x cm?
  
  To solve this problem, remember that the perimeter of a rectangle is the sum of the lengths of all its sides. Since in a rectangle the opposite sides are equal, then P = 2 * (a + b), where a is the length, b is the width. Let the width of the rectangle be x cm, then the length of the rectangle is 2x cm. Knowing. that the perimeter is 126 centimeters, let’s make the equation.
  2 * (x + 2x) = 126;
  2 * 3x = 126;
  6x = 126;
  x = 126/6;
  x = 21 centimeters.
  Answer: 21 centimeters.
  
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