Question

the length of a rectangle is 8 m less than thrice it's width if area of the rectangle is 1675 sq m them find the length and width of the rectangle

Answer 1

Solution :

Let breadth of the rectangle( b ) = x m

length ( l ) = ( 3x - 8 ) m

Area = 1675 sq m ( given )

=> l × b = 1675

=> ( 3x - 8 ) x = 1675

=> 3x² - 8x - 1675 = 0

=> 3x² -75x + 67x - 1675 = 0

=> 3x( x - 25 ) + 67 ( x - 25 ) = 0

=> ( x - 25 )( 3x + 67 ) = 0

=> x - 25 = 0 or 3x + 67 = 0

=> x = 25 or 3x = -67

=> x = 25 or x = -67/3

x should not be negative .

Therefore ,

b = x = 25 m

l = ( 3x - 8 )

= 3 × 25 - 8

= 75 - 8

l = 67 m

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