The length of the rectangular piece of land was increased by 30% and the width by 20%

The length of the rectangular piece of land was increased by 30% and the width by 20%, resulting in an increase in its area of 28 m². Determine the area of the original site.

The area of a rectangular area is found by the formula:
S = a * b. Let’s denote the area of the original plot of land x. After the changes, the area of the new site became:
S = 1.3a * 1.2b = x + 28.
We get a system of two equations:
a * b = x
1.56 * a * b = x + 28

Substitute x in the second equation and solve:
1.56ab = ab + 28
0.56ab = 28
ab = 50 (m²) – this is the original area of the site.
Answer: the area of the original site was 50 m².