A square with a side of 9 cm was cut out of a rectangle with a width of 1.8 dm and a length of 1.4

A square with a side of 9 cm was cut out of a rectangle with a width of 1.8 dm and a length of 1.4 times the width. Find the area of the remaining figure?

1) Determine the length of this rectangle. To do this, we will increase the width by 1.4 times: 1.8 · 1.4 = 2.52 (dm);

2) Calculate the area of this rectangle using the formula: S = a b = 1.8 2.52 = 4.536 (dm ^ 2);

3) Let us express the size of the side of the square in decimeters (9 cm = 0.9 dm) and find the area of the cut out square using the formula: S = a ^ 2 = 0.9 ^ 2 = 0.81 (dm ^ 2);

4) Subtract the area of the square from the area of the rectangle and determine the area of the remaining figure: 4.536 – 0.81 = 3.726 (dm ^ 2).

Answer: the area of the remaining figure is 3.726 dm ^ 2.