The area of a rectangle is equal to the area of a square whose diagona...
d = a√2
12√2 = a√2
a = 12
l * b = a² = (12²) = 144
l – b = 7 ; l = b + 7
(b + 7)*(b) = 144
b² + 7b – 144 = 0
b = 9; l = 16
2(l + b) = 2(16 + 9) = 50m
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The area of a rectangle is equal to the area of a square whose diagona...
Understanding the Problem
To find the perimeter of the rectangle, we first need to determine its dimensions based on the information given.
Step 1: Find the Area of the Square
- The diagonal of the square is given as 12√2 metres.
- Using the relationship between the side (s) and the diagonal (d) of a square: d = s√2.
- Thus, s = d/√2 = (12√2)/√2 = 12 metres.
- The area of the square = s² = 12² = 144 square metres.
Step 2: Set Up the Rectangle's Dimensions
- Let the length of the rectangle be L and the breadth be B.
- We know that the area of the rectangle = L × B = 144 square metres.
- We're also given that the difference between the length and the breadth is 7 metres: L - B = 7.
Step 3: Solve the Equations
- From L - B = 7, we can express L as: L = B + 7.
- Substitute L in the area equation: (B + 7) × B = 144.
- Expanding this gives: B² + 7B - 144 = 0.
Step 4: Factor the Quadratic Equation
- We need to factor B² + 7B - 144.
- The factors are (B + 16)(B - 9) = 0.
- Thus, B = 9 (since breadth cannot be negative) and L = B + 7 = 9 + 7 = 16 metres.
Step 5: Calculate the Perimeter
- The perimeter (P) of the rectangle is given by the formula: P = 2(L + B).
- Substitute L and B: P = 2(16 + 9) = 2 × 25 = 50 metres.
Conclusion
- The perimeter of the rectangle is 50 metres, which corresponds to option 'B'.
The area of a rectangle is equal to the area of a square whose diagona...
Ya answer is correct. I calculated.