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The base of an isosceles triangle is 24 ...

The base of an isosceles triangle is 24 cm and its area is `60 cm^(2) `Find its perimeter.

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To find the perimeter of the isosceles triangle with a base of 24 cm and an area of 60 cm², we can follow these steps: ### Step 1: Understand the triangle We have an isosceles triangle ABC with base BC = 24 cm. The area of the triangle is given as 60 cm². ### Step 2: Use the area formula The area (A) of a triangle can be calculated using the formula: \[ A = \frac{1}{2} \times \text{base} \times \text{height} \] Here, the base (BC) = 24 cm and the area = 60 cm². ### Step 3: Set up the equation Substituting the known values into the area formula: \[ 60 = \frac{1}{2} \times 24 \times h \] where \( h \) is the height from point A to the base BC. ### Step 4: Solve for height (h) To isolate \( h \), we can rearrange the equation: \[ 60 = 12h \quad \Rightarrow \quad h = \frac{60}{12} = 5 \text{ cm} \] So, the height (AD) from point A to the base BC is 5 cm. ### Step 5: Find the lengths of the equal sides (AC and AB) Since D is the midpoint of BC, we have: \[ BD = DC = \frac{24}{2} = 12 \text{ cm} \] Now, we can use the Pythagorean theorem in triangle ABD: \[ AB^2 = AD^2 + BD^2 \] Substituting the known values: \[ AB^2 = 5^2 + 12^2 = 25 + 144 = 169 \] Taking the square root gives: \[ AB = \sqrt{169} = 13 \text{ cm} \] Since the triangle is isosceles, AC = AB = 13 cm. ### Step 6: Calculate the perimeter The perimeter (P) of triangle ABC is given by: \[ P = AB + BC + AC \] Substituting the values we found: \[ P = 13 + 24 + 13 = 50 \text{ cm} \] ### Final Answer The perimeter of the triangle is **50 cm**. ---
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