Questions: Solve the following triangle.
B=45°, C=64°, b=39 inches
A= (Simplify your answer.)
Transcript text: Solve the following triangle.
\[
B=45^{\circ}, C=64^{\circ}, b=39 \text { inches }
\]
$A=$ $\square$ $\cdot$ (Simplify your answer.)
Solution
Solution Steps
To solve the triangle, we can use the fact that the sum of angles in a triangle is \(180^\circ\). First, find angle \(A\) by subtracting the given angles \(B\) and \(C\) from \(180^\circ\). Then, use the Law of Sines to find the length of side \(a\).
Step 1: Calculate Angle \( A \)
To find angle \( A \), we use the fact that the sum of the angles in a triangle is \( 180^\circ \):
\[
A = 180^\circ - B - C = 180^\circ - 45^\circ - 64^\circ = 71^\circ
\]
Step 2: Apply the Law of Sines
Using the Law of Sines, we can find the length of side \( a \):
\[
\frac{a}{\sin(A)} = \frac{b}{\sin(B)}
\]
Substituting the known values:
\[
\frac{a}{\sin(71^\circ)} = \frac{39}{\sin(45^\circ)}
\]
Step 3: Solve for Side \( a \)
Rearranging the equation to solve for \( a \):
\[
a = b \cdot \frac{\sin(A)}{\sin(B)} = 39 \cdot \frac{\sin(71^\circ)}{\sin(45^\circ)} \approx 52.1494
\]
Final Answer
The values we found are:
\[
A = 71^\circ \quad \text{and} \quad a \approx 52.1494
\]
Thus, the final boxed answers are:
\[
\boxed{A = 71^\circ}
\]
\[
\boxed{a \approx 52.1494}
\]