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If tan x^(@) = (5)/(12), tan y = (3)/(4)...

If `tan x^(@) = (5)/(12), tan y = (3)/(4)` and AB = 48 m. Find the length of CD.

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To solve the problem step by step, we will use the given information about the tangents of angles and the length of AB to find the length of CD. ### Step 1: Understand the Problem We are given: - \( \tan x = \frac{5}{12} \) - \( \tan y = \frac{3}{4} \) - Length of \( AB = 48 \, \text{m} \) We need to find the length of \( CD \). ### Step 2: Set Up the Triangle Let's denote: - \( CD = P \) - \( BC = x \) From the triangle, we can express the tangent functions in terms of \( P \) and \( x \). ### Step 3: Use the Tangent Function for Angle \( x \) For angle \( x \): \[ \tan x = \frac{P}{AB + BC} = \frac{P}{48 + x} \] Given \( \tan x = \frac{5}{12} \), we can set up the equation: \[ \frac{5}{12} = \frac{P}{48 + x} \] ### Step 4: Rearranging the Equation Cross-multiplying gives: \[ 5(48 + x) = 12P \] Expanding this: \[ 240 + 5x = 12P \quad \text{(Equation 1)} \] ### Step 5: Use the Tangent Function for Angle \( y \) For angle \( y \): \[ \tan y = \frac{P}{x} \] Given \( \tan y = \frac{3}{4} \), we can set up the equation: \[ \frac{3}{4} = \frac{P}{x} \] ### Step 6: Rearranging the Equation for Angle \( y \) Cross-multiplying gives: \[ 3x = 4P \quad \text{(Equation 2)} \] ### Step 7: Substitute Equation 2 into Equation 1 From Equation 2, we can express \( x \) in terms of \( P \): \[ x = \frac{4P}{3} \] Now, substitute \( x \) in Equation 1: \[ 240 + 5\left(\frac{4P}{3}\right) = 12P \] This simplifies to: \[ 240 + \frac{20P}{3} = 12P \] ### Step 8: Clear the Fraction Multiply the entire equation by 3 to eliminate the fraction: \[ 720 + 20P = 36P \] ### Step 9: Rearranging to Solve for \( P \) Rearranging gives: \[ 720 = 36P - 20P \] \[ 720 = 16P \] ### Step 10: Solve for \( P \) Dividing both sides by 16: \[ P = \frac{720}{16} = 45 \] ### Conclusion The length of \( CD \) is \( 45 \, \text{m} \).
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