SOLUTION: The area of the rectangular plot is 140m^2. The length of the plot (in metres) is one less than three times its breadth. We have to find length & breadth pf the plot.

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Question 715247: The area of the rectangular plot is 140m^2. The length of the plot (in metres) is one less than three times its breadth. We have to find length & breadth pf the plot.
Answer by mananth(16946) About Me  (Show Source):
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The area of the rectangular plot is 140m^2. The length of the plot (in metres) is one less than three times its breadth. We have to find length & breadth pf the plot
let breadth be x
length is 3x-1
Area = 140+m%5E2
Area of rectangle = L * B
140 =x(3x-1)
140+=+3x%5E2-x
3x%5E2-x-140=0
Find the roots of the equation by quadratic formula
-1
a= 3 b= -1 c= -140
-1680
b^2-4ac= 1 -
b^2-4ac= 1681 sqrt%28%091681%09%29= 41
x=%28-b%2B-sqrt%28b%5E2-4ac%29%29%2F%282a%29
x1=%28-b%2Bsqrt%28b%5E2-4ac%29%29%2F%282a%29 41
x1=( 1 + )/ 6
x1= 7 ) /
x2=( 1 -41 6
x2= -6.67
Ignore negative value mph
x = 7
breadth = 7
length = 3(7) -1= 20
The dimensions are 7 & 20 m