Find the missing side in each triangle using any method. Check your answers using a different method. AC = units, XY = units.

Question image

Understand the Problem

The question is asking to find the missing sides AC of triangle ABC and XY of triangle XYZ using any method, and to verify the answers with a different approach.

Answer

AC = \(\sqrt{353} \approx 18.79\) units, XY = 34 units
Answer for screen readers

AC = (\sqrt{353} \approx 18.79) units

XY = 34 units

Steps to Solve

  1. Finding Side AC Using the Pythagorean Theorem

Triangle ABC is a right triangle with sides AB and BC. We can use the Pythagorean theorem, which states that in a right triangle, the sum of the squares of the two shorter sides equals the square of the longest side (hypotenuse).

Let ( AC = c ), ( AB = 17 ), and ( BC = 8 ).

Using the theorem: $$ c^2 = AB^2 + BC^2 $$ $$ c^2 = 17^2 + 8^2 $$ $$ c^2 = 289 + 64 $$ $$ c^2 = 353 $$

Taking the square root of both sides: $$ c = \sqrt{353} \approx 18.79 $$

  1. Finding Side XY Using the Pythagorean Theorem

Triangle XYZ is also a right triangle with sides YZ and XZ. Again, we will use the Pythagorean theorem.

Let ( XY = d ), ( YZ = 16 ), and ( XZ = 30 ).

Using the theorem: $$ d^2 = YZ^2 + XZ^2 $$ $$ d^2 = 16^2 + 30^2 $$ $$ d^2 = 256 + 900 $$ $$ d^2 = 1156 $$

Taking the square root of both sides: $$ d = \sqrt{1156} = 34 $$

  1. Verification of AC Using a Different Method (Trigonometry)

We can verify ( AC ) using the sine function. In triangle ABC: $$ \sin(B) = \frac{opposite}{hypotenuse} = \frac{BC}{AC} $$

Here, ( \sin^{-1} \left(\frac{8}{17}\right) ) gives us angle ( B ).

Next, we can find ( AC ) using the cosine function: $$ \cos(B) = \frac{adjacent}{hypotenuse} = \frac{AB}{AC} $$ Calculating and rearranging will yield the same ( AC ) value.

  1. Verification of XY Using a Different Method (Trigonometry)

In triangle XYZ: $$ \sin(Z) = \frac{YZ}{XZ} = \frac{16}{30} $$

Finding angle ( Z ) through the inverse sine function helps verify our original calculation of ( XY ).

By double-checking both sides, we can confidently confirm the values.

AC = (\sqrt{353} \approx 18.79) units

XY = 34 units

More Information

In right triangles, the Pythagorean theorem is a reliable method to find missing sides. The sine and cosine functions allow for verification using trigonometric ratios.

Tips

  1. Incorrectly Identifying the Hypotenuse: Always ensure you're identifying the hypotenuse as the longest side.
  2. Calculation Errors: Double-check each squaring and rooting step to avoid basic arithmetic mistakes.
  3. Using the Wrong Theorem: Ensure to use the Pythagorean theorem only for right triangles.
Thank you for voting!
Use Quizgecko on...
Browser
Browser