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If in a triangle with sides a, b & c, (s...

If in a triangle with sides a, b & c, `(s-a)=5cm,(s-b)=10cm&(s-c)=1cm` find area of the triangle.

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To find the area of the triangle given the conditions \(s-a=5 \, \text{cm}\), \(s-b=10 \, \text{cm}\), and \(s-c=1 \, \text{cm}\), we can follow these steps: ### Step 1: Express \(a\), \(b\), and \(c\) in terms of \(s\) From the given equations: - \(s - a = 5\) implies \(a = s - 5\) - \(s - b = 10\) implies \(b = s - 10\) - \(s - c = 1\) implies \(c = s - 1\) ### Step 2: Find the semi-perimeter \(s\) The semi-perimeter \(s\) is defined as: \[ s = \frac{a + b + c}{2} \] Substituting the expressions for \(a\), \(b\), and \(c\): \[ s = \frac{(s - 5) + (s - 10) + (s - 1)}{2} \] This simplifies to: \[ s = \frac{3s - 16}{2} \] Multiplying both sides by 2: \[ 2s = 3s - 16 \] Rearranging gives: \[ s = 16 \, \text{cm} \] ### Step 3: Calculate \(a\), \(b\), and \(c\) Now substituting \(s = 16\) back into the expressions for \(a\), \(b\), and \(c\): - \(a = s - 5 = 16 - 5 = 11 \, \text{cm}\) - \(b = s - 10 = 16 - 10 = 6 \, \text{cm}\) - \(c = s - 1 = 16 - 1 = 15 \, \text{cm}\) ### Step 4: Use Heron's formula to find the area Heron's formula states that the area \(A\) of a triangle can be calculated as: \[ A = \sqrt{s(s-a)(s-b)(s-c)} \] Substituting the values we have: \[ A = \sqrt{16 \times (16 - 11) \times (16 - 6) \times (16 - 15)} \] Calculating each term: - \(s - a = 5\) - \(s - b = 10\) - \(s - c = 1\) Thus, we have: \[ A = \sqrt{16 \times 5 \times 10 \times 1} \] Calculating the product: \[ A = \sqrt{800} \] Breaking it down: \[ 800 = 16 \times 50 = 16 \times 25 \times 2 \] Taking the square root: \[ A = \sqrt{16} \times \sqrt{25} \times \sqrt{2} = 4 \times 5 \times \sqrt{2} = 20\sqrt{2} \, \text{cm}^2 \] ### Final Answer The area of the triangle is: \[ \boxed{20\sqrt{2} \, \text{cm}^2} \]
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