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The perimeter of an equilateral triangle...

The perimeter of an equilateral triangle is 60m. The area is

A

`10sqrt(3)m^(2)`

B

`15sqrt(3)m^(2)`

C

`20sqrt(3)m^(2)`

D

`100sqrt(3)m^(2)`

Text Solution

AI Generated Solution

The correct Answer is:
To find the area of an equilateral triangle given its perimeter, we can follow these steps: ### Step-by-Step Solution: 1. **Identify the given information**: - The perimeter of the equilateral triangle is given as 60 meters. 2. **Determine the length of one side**: - Since it is an equilateral triangle, all three sides are equal. Let the length of one side be \( A \). - The formula for the perimeter \( P \) of an equilateral triangle is: \[ P = 3A \] - Setting this equal to the given perimeter: \[ 3A = 60 \] - To find \( A \), divide both sides by 3: \[ A = \frac{60}{3} = 20 \text{ meters} \] 3. **Use the formula for the area of an equilateral triangle**: - The area \( A_t \) of an equilateral triangle can be calculated using the formula: \[ A_t = \frac{\sqrt{3}}{4} A^2 \] - Substitute \( A = 20 \) into the formula: \[ A_t = \frac{\sqrt{3}}{4} \times (20)^2 \] 4. **Calculate \( A^2 \)**: - Calculate \( 20^2 \): \[ 20^2 = 400 \] 5. **Substitute \( A^2 \) back into the area formula**: - Now substitute \( 400 \) into the area formula: \[ A_t = \frac{\sqrt{3}}{4} \times 400 \] 6. **Simplify the area**: - Calculate \( \frac{400}{4} \): \[ \frac{400}{4} = 100 \] - Therefore, the area is: \[ A_t = 100\sqrt{3} \text{ square meters} \] ### Final Answer: The area of the equilateral triangle is \( 100\sqrt{3} \) square meters. ---
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