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A right-angled triangle has a width of x cm. The length of the hypotenuse is 10 cm. The perimeter of the triangle is 24cm. Find the area of the triangle

User Matt Mower
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The area of the right-angled triangle is
\( 24 \, \text{cm}^2 \).

The length of the hypotenuse is given as 10 cm. The perimeter of the triangle is the sum of the three sides:


\[ \text{Perimeter} = \text{Width} + \text{Height} + \text{Hypotenuse} \]

Given that the perimeter is 24 cm, we can set up the equation:


\[ x + \text{Height} + 10 = 24 \]

Now, solve for the height
(\(\text{Height}\)):


\[ \text{Height} = 24 - x - 10 \]


\[ \text{Height} = 14 - x \]

Now, we can use the Pythagorean theorem to relate the width, height, and hypotenuse:


\[ x^2 + (\text{Height})^2 = \text{Hypotenuse}^2 \]

Substitute the expression for height:


\[ x^2 + (14 - x)^2 = 10^2 \]

Now, solve for x:


\[ x^2 + (196 - 28x + x^2) = 100 \]


\[ 2x^2 - 28x + 96 = 0 \]

Divide the entire equation by 2 to simplify:


\[ x^2 - 14x + 48 = 0 \]

Now, factor the quadratic equation:


\[ (x - 6)(x - 8) = 0 \]

So,
\( x = 6 \) or
\( x = 8 \). Since the width cannot be negative, we take
\( x = 8 \) cm.

Now that we have the width
(\( x = 8 \)) and the height
(\( \text{Height} = 14 - x = 14 - 8 = 6 \)), we can find the area
(\( A \)) of the right-angled triangle using the formula:


\[ A = (1)/(2) * \text{Width} * \text{Height} \]

Substitute the values:


\[ A = (1)/(2) * 8 * 6 \]


\[ A = 24 \]

Therefore, the area of the right-angled triangle is
\( 24 \, \text{cm}^2 \).

User Aaron Hathaway
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