The length and width of one iron sheet together are 2130 mm. What is the area of the sheet if the length is 2 times the width?

To solve this problem, we introduce two conditional variables “X” and “Y”, through which we denote the length and width of the iron sheet, respectively.
Then, based on the data of the problem, we compose the following equations:
1) X + Y = 2130;
2) X / Y = 2.
Solving a system of two equations with two unknowns, we obtain X = 2Y.
Substituting X in the first equation, we get 2Y + Y = 2130 or 3Y = 2130 or Y = 2130/3 = 710 mm.
Therefore, X will be equal to 710 x 2 = 1420 mm.
This means that the area of the iron sheet will be equal to 1420 x 710 = 1008200 mm ^ 2.
Answer: 1008200 mm ^ 2.