The dimensions of the rectangle are (2y – 7) units by (2y + 7) units
The formula for calculating the area of a rectangle is expressed as
Area = length * width
Given the following parameter
Area = .4y² - 49
Factorize the area
Area = (2y)² - 7²
Using the difference of two square
Area = (2y - 7)(2 y + 7)
Hence the dimensions of the rectangle are (2y – 7) units by (2y + 7) units
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