A rectangular field is 20m long and 14m wide. There is a path of equal width all around it.having an area 111sq.m find the width of the path
Answers
Answer:
Step-by-step explanation:
Solution :-
Let the width of the path be x m.
Then, the length of the path be 20 + 2x m.
And the width of the path be 14 + 2x m.
According to the Question,
Area of rectangular path = Length × Breadth
= (20 + 2x) (14 + 2x)
= 4x² + 68x + 280
Area of the path = 111 m²
⇒ 4x² + 68x + 280 = 111 m²
Subtracting 280 from left side,
⇒ 4x² + 68x + 280 - 280 = 111 m²
⇒ 4x² + 68x = 111 m²
⇒ 4x² + 68x - 111 = 0
⇒ 4x² + 74x - 6x - 111 = 0
⇒ 2x(2x + 37) - 3(2x + 37) = 0
⇒ (2x + 37) (2x - 3) = 0
⇒ x = - 37/2, 3/2 = 0
⇒ x = - 18.5, 1.5 (As x can't be negative)
⇒ x = 1.5 m
Hence, the width of the path is 1.5 m.
ANSWER:
Given
- Length of rectangular field = 20m
- Width of rectangular field = 14m
- Area of path = 111 m²
- Let the width of the path be 'x'
- Then the length of path will be 20 + 2x
- And width will be 14 + 2x
Area of rectangular path = length × Breadth
→ 111m² = (20 + 2x) (14 + 2x)
→ 111m² = 280 + 40x + 28x + 4x²
→ 111m² = 4x² + 68x + 280
Subtracting 280 on LHS
→ 4x² + 68x + 280 - 280 = 111
→ 4x² + 68x - 111 = 0
Now , we get a quadratic equation
Solving using factorisation
Splitting the middle term
→ 4x² + 74x - 6x - 111 = 0
→ 2x(2x + 37) - 3(2x + 34) = 0
→ (2x + 37)(2x - 3) = 0
2x + 37 = 9
x = -37/2 = - 18.5
_________________
2x - 3 = 0
x = 3/2 = 1.5
x = - 18.5 , 1.5
Hence distance can't be negative
♦ x = 1.5
Hence, width of the path = 1.5m