the length of a rectangle is three metre more than its width. if both length and width are decreased by 2 metre and the area is deceased by 18 square metre. find the dimensions of the rectangle
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Let the width of rectangle = x m
length = x+3 m
Area = x(x+3) = (x²+3x) m²
If both length and width are reduced by 2 meters
width = x-2 m
length = (x+3) - 2 = x+1 m
Area = (x-2)(x+1) = (x² - x - 2) m²
Decrease in area =(x²+3x) m² - (x² - x - 2) m² = 4x+2 m²
given that decrease is 18m²
So 4x+2 = 18
⇒ 4x = 18-2 = 16
⇒ x = 16/4
⇒ x = 4m (width)
length = x+3 = 4+3 = 7m
Length = 7m, width = 4m
length = x+3 m
Area = x(x+3) = (x²+3x) m²
If both length and width are reduced by 2 meters
width = x-2 m
length = (x+3) - 2 = x+1 m
Area = (x-2)(x+1) = (x² - x - 2) m²
Decrease in area =(x²+3x) m² - (x² - x - 2) m² = 4x+2 m²
given that decrease is 18m²
So 4x+2 = 18
⇒ 4x = 18-2 = 16
⇒ x = 16/4
⇒ x = 4m (width)
length = x+3 = 4+3 = 7m
Length = 7m, width = 4m
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