The area of rectangle whose length is five more than twice of breadth is 75 sq.cm. Find the length
Answers
Answer:
Let the width of the rectangle = x units
Length = (2 x + 5) units
According to the question,
Area = x(2x + 5)
=> 75 = 2x2+5x
=> 2x2+5x−75=0
=> 2x2+15x−10x−75=0
=> x(2x+15)-5(2x+15)=0
=> (2x+15)(x-5)=0
=> x = 5 and −152
Width cannot be negative.
Width = 5 units
Length=2x+5 =2×5+5=15 units
Perimeter of the rectangle
= 2(15 + 5) = 40 units
ANSWER:
- Length of rectangle = 15 cm
- Breadth of rectangle = 5 cm
GIVEN:
- Area of rectangle = 75 cm²
- Length is five more than twice of breadth.
TO FIND:
- Length of rectangle.
SOLUTION:
Let the breadth of rectangle be x
Length of rectangle = 2x+5
Formula:
Area of rectangle = Length*Breadth.
=> 75 cm² = (2x+5)(x)
=> 2x²+5x = 75 cm²
=> 2x²+5x-75 = 0
=> 2x²+15x-10x-75 = 0
=> (2x²-10x)+(15x-75) = 0
=> 2x(x-5) +15(x-5) = 0
=> (x-5)(2x+15) = 0
Either (2x+15) = 0
=> 2x = -15
=> x = -15/2
This is not possible as breadth can't be negative.
Either (x-5) = 0
=> x = 5
Breadth = 5
Length = 2x+5
= 2(5)+5
= 15
Length of rectangle = 15 cm
Breadth of rectangle = 5 cm