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The number of triangles with each side h...

The number of triangles with each side having integral length and the longest side is of 11 units is equal to `k^(2)`, then the value of 'k' is equal to

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To find the number of triangles with integral side lengths where the longest side is 11 units, we can follow these steps: ### Step-by-Step Solution: 1. **Understanding the Triangle Inequality**: For any triangle with sides \(a\), \(b\), and \(c\) (where \(c\) is the longest side), the triangle inequality states that: - \(a + b > c\) - \(a > 0\) - \(b > 0\) Here, we set \(c = 11\). Therefore, we need to satisfy: - \(a + b > 11\) - \(a > 0\) - \(b > 0\) 2. **Setting Constraints for \(a\) and \(b\)**: Since \(c = 11\) is the longest side, both \(a\) and \(b\) must be less than or equal to 11: - \(1 \leq a \leq 11\) - \(1 \leq b \leq 11\) 3. **Finding Possible Values for \(a\)**: We will consider each possible value of \(a\) from 1 to 11 and determine the corresponding values of \(b\) such that \(a + b > 11\). - **If \(a = 11\)**: \[ b > 11 - 11 \implies b > 0 \quad \text{(possible values: 1 to 11)} \quad \text{(11 values)} \] - **If \(a = 10\)**: \[ b > 11 - 10 \implies b > 1 \quad \text{(possible values: 2 to 11)} \quad \text{(10 values)} \] - **If \(a = 9\)**: \[ b > 11 - 9 \implies b > 2 \quad \text{(possible values: 3 to 11)} \quad \text{(9 values)} \] - **If \(a = 8\)**: \[ b > 11 - 8 \implies b > 3 \quad \text{(possible values: 4 to 11)} \quad \text{(8 values)} \] - **If \(a = 7\)**: \[ b > 11 - 7 \implies b > 4 \quad \text{(possible values: 5 to 11)} \quad \text{(7 values)} \] - **If \(a = 6\)**: \[ b > 11 - 6 \implies b > 5 \quad \text{(possible values: 6 to 11)} \quad \text{(6 values)} \] - **If \(a = 5\)**: \[ b > 11 - 5 \implies b > 6 \quad \text{(possible values: 7 to 11)} \quad \text{(5 values)} \] - **If \(a = 4\)**: \[ b > 11 - 4 \implies b > 7 \quad \text{(possible values: 8 to 11)} \quad \text{(4 values)} \] - **If \(a = 3\)**: \[ b > 11 - 3 \implies b > 8 \quad \text{(possible values: 9 to 11)} \quad \text{(3 values)} \] - **If \(a = 2\)**: \[ b > 11 - 2 \implies b > 9 \quad \text{(possible values: 10 to 11)} \quad \text{(2 values)} \] - **If \(a = 1\)**: \[ b > 11 - 1 \implies b > 10 \quad \text{(possible value: 11)} \quad \text{(1 value)} \] 4. **Calculating Total Combinations**: Now, we sum all the possible values of \(b\) for each corresponding \(a\): \[ 11 + 10 + 9 + 8 + 7 + 6 + 5 + 4 + 3 + 2 + 1 = 66 \] 5. **Finding \(k\)**: We are given that the number of triangles is equal to \(k^2\): \[ k^2 = 66 \] Thus, \(k = \sqrt{66}\). ### Final Answer: The value of \(k\) is \( \sqrt{66} \).
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