In a rectangle, the width is 6 cm less than the length, and the length is 1.4 times the width. How long is the rectangle?

1. We take the length of the rectangle for x, for the width of the rectangle.

2. We compose the equations:

x – y = 6;

x / y = 1.4; x = 1.4y; The resulting value of x is substituted into the first equation:

1.4y – y = 6;

0.4 y = 6;

y = 6: 0.4 = 15;

x = 1.4 x 15 = 21.

Answer: the length of the rectangle is 21 centimeters.