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The perimeter of a right triangle is 24 cm. If its hypotenuse is 10 cm, find the other two sides. Find its area by using the formula area of a right triangle. Verify your result by using Heron's formula.​

User Dayzza
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Answer: Let the two legs of the right triangle be a and b. Then, using the Pythagorean theorem, we have:

a^2 + b^2 = 10^2 = 100

The perimeter of the triangle is:

a + b + 10 = 24

Solving for a and b in terms of one variable, we get:

a = 24 - b - 10 = 14 - b

b = 24 - a - 10 = 14 - a

Substituting these expressions into the Pythagorean equation, we get:

(14 - b)^2 + b^2 = 100

Expanding and simplifying, we get a quadratic equation:

2b^2 - 28b + 84 = 0

Dividing by 2, we get:

b^2 - 14b + 42 = 0

This quadratic can be factored as:

(b - 7)(b - 6) = 0

Therefore, b = 7 or b = 6.

If b = 7, then a = 14 - 7 = 7. If b = 6, then a = 14 - 6 = 8.

So the other two sides of the right triangle are 7 cm and 24 - 7 - 10 = 7 cm, or 6 cm and 24 - 6 - 10 = 8 cm.

Using the formula for the area of a right triangle, we have:

Area = (1/2) * base * height = (1/2) * 7 * 7 = 24.5 cm^2 (for the triangle with legs 7 cm and 7 cm) or (1/2) * 6 * 8 = 24 cm^2 (for the triangle with legs 6 cm and 8 cm)

To verify the result using Heron's formula, we need to calculate the semi-perimeter of the triangle. It is:

s = (7 + 7 + 10)/2 = 12

Using Heron's formula, the area is:

sqrt(s(s-7)(s-7)(s-10)) = sqrt(12552) = sqrt(600) = 24.49 cm^2 (for the triangle with legs 7 cm and 7 cm) or sqrt(12642) = sqrt(576) = 24 cm^2 (for the triangle with legs 6 cm and 8 cm)

As we can see, the results obtained using the two methods are very close to each other, which confirms the correctness of our solution.

Explanation:

User Youssef
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