Math Problem Statement

Solve the following oblique triangle for all of its missing sides & angles. Round all answers to the nearest whole number.

Solve the following oblique triangle for all of its missing sides & angles. Round all answers to the nearest whole number.

Solution

The given triangle is an oblique triangle, where we have:

  • Side a=192a = 192
  • Side b=122b = 122
  • Angle C=22.2C = 22.2^\circ

To solve the triangle, we need to find the missing sides cc and the angles AA and BB.

Step 1: Use the Law of Cosines

Since we have two sides and an included angle (SAS case), we can use the Law of Cosines to find the third side cc:

c2=a2+b22abcos(C)c^2 = a^2 + b^2 - 2ab \cdot \cos(C)

Substituting the given values:

c2=1922+12222(192)(122)cos(22.2)c^2 = 192^2 + 122^2 - 2(192)(122) \cdot \cos(22.2^\circ)

c2=36864+148842(192)(122)0.92718c^2 = 36864 + 14884 - 2(192)(122) \cdot 0.92718

c2=36864+1488443262.5c^2 = 36864 + 14884 - 43262.5

c2=5174843262.5=8485.5c^2 = 51748 - 43262.5 = 8485.5

c=8485.592.1c = \sqrt{8485.5} \approx 92.1

So, the third side is c92c \approx 92.

Step 2: Use the Law of Sines to Find Angle AA

Now that we know all three sides, we can use the Law of Sines to find the other angles. The Law of Sines states:

sinAa=sinCc\frac{\sin A}{a} = \frac{\sin C}{c}

Rearranging to solve for AA:

sinA=asinCc\sin A = \frac{a \cdot \sin C}{c}

Substitute the known values:

sinA=192sin(22.2)92\sin A = \frac{192 \cdot \sin(22.2^\circ)}{92}

sinA=1920.37792=72.3892=0.7867\sin A = \frac{192 \cdot 0.377}{92} = \frac{72.38}{92} = 0.7867

Now, take the inverse sine:

A=arcsin(0.7867)51.7A = \arcsin(0.7867) \approx 51.7^\circ

So, angle A52A \approx 52^\circ.

Step 3: Find Angle BB

The sum of the angles in any triangle is 180180^\circ. So, to find angle BB, we subtract the known angles AA and CC from 180180^\circ:

B=180AC=1805222.2=105.8B = 180^\circ - A - C = 180^\circ - 52^\circ - 22.2^\circ = 105.8^\circ

So, angle B106B \approx 106^\circ.

Summary of Results:

  • Side c92c \approx 92
  • Angle A52A \approx 52^\circ
  • Angle B106B \approx 106^\circ

Let me know if you would like further details or clarifications!

Here are some related questions you might explore:

  1. What happens if one of the sides is larger than the sum of the other two?
  2. How can we verify the solution using only the Law of Cosines?
  3. How would the process change if all angles were given, but no sides?
  4. How does rounding intermediate results affect the final answers?
  5. How can the Law of Sines help solve ambiguous cases (SSA)?

Tip: Always double-check the sum of angles in a triangle to ensure they add up to 180180^\circ.

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Math Problem Analysis

Mathematical Concepts

Trigonometry
Law of Cosines
Law of Sines

Formulas

Law of Cosines: c^2 = a^2 + b^2 - 2ab * cos(C)
Law of Sines: sin(A)/a = sin(C)/c

Theorems

Law of Cosines
Law of Sines

Suitable Grade Level

Grades 10-12