Triangle [tex]$ABC$[/tex] is a right triangle and [tex]$\cos \left(22.6^{\circ}\right)=\frac{b}{13}$[/tex].

Solve for [tex]$b$[/tex] and round to the nearest whole number.

Which equation correctly uses the value of [tex]$b$[/tex] to solve for [tex]$a$[/tex]?

A. [tex]$\tan \left(22.6^{\circ}\right)=\frac{a}{13}$[/tex]
B. [tex]$\tan \left(22.6^{\circ}\right)=\frac{13}{a}$[/tex]
C. [tex]$\tan \left(22.6^{\circ}\right)=\frac{a}{12}$[/tex]
D. [tex]$\tan \left(22.6^{\circ}\right)=\frac{12}{a}$[/tex]



Answer :

To solve the given problem, we start by addressing the cosine and tangent relationships within the right triangle.

Step 1: Solve for [tex]\( b \)[/tex] using [tex]\(\cos(22.6^\circ) = \frac{b}{13}\)[/tex]

Given:
[tex]\[ \cos(22.6^\circ) = \frac{b}{13} \][/tex]

To find [tex]\( b \)[/tex]:
[tex]\[ b = 13 \cdot \cos(22.6^\circ) \][/tex]

Given that the result is approximately:
[tex]\[ b \approx 12 \][/tex]

After rounding, [tex]\( b \)[/tex] to the nearest whole number is [tex]\( 12 \)[/tex].

Step 2: Identify the correct equation using the value of [tex]\( b \)[/tex] and the tangent function to solve for [tex]\( a \)[/tex]

We need to find which of the given equations involving [tex]\(\tan(22.6^\circ)\)[/tex] is correctly related to the sides of the triangle.

Equation Analysis:

1. [tex]\(\tan(22.6^\circ) = \frac{a}{13}\)[/tex]

Evaluate:
[tex]\[ a = 13 \cdot \tan(22.6^\circ) \approx 5.411 \][/tex]

2. [tex]\(\tan(22.6^\circ) = \frac{13}{a}\)[/tex]

Evaluate:
[tex]\[ a = \frac{13}{\tan(22.6^\circ)} \approx 31.230 \][/tex]

3. [tex]\(\tan(22.6^\circ) = \frac{a}{12}\)[/tex]

Evaluate:
[tex]\[ a = 12 \cdot \tan(22.6^\circ) \approx 4.995 \][/tex]

4. [tex]\(\tan(22.6^\circ) = \frac{12}{a}\)[/tex]

Evaluate:
[tex]\[ a = \frac{12}{\tan(22.6^\circ)} \approx 28.828 \][/tex]

These values are derived based on the tangent function of the given angle.

Conclusion:
By evaluating the tangent relationships:
- [tex]\(\tan(22.6^\circ) = \frac{a}{13}\)[/tex] gives [tex]\( a \approx 5.411 \)[/tex]
- [tex]\(\tan(22.6^\circ) = \frac{13}{a}\)[/tex] gives [tex]\( a \approx 31.230 \)[/tex]
- [tex]\(\tan(22.6^\circ) = \frac{a}{12}\)[/tex] gives [tex]\( a \approx 4.995 \)[/tex]
- [tex]\(\tan(22.6^\circ) = \frac{12}{a}\)[/tex] gives [tex]\( a \approx 28.828 \)[/tex]

The accurate solution based on these calculations corresponds to the relationships given and the values derived. Therefore, we verify which value makes sense for a right triangle with [tex]\( \cos \left(22.6^\circ\right)=\frac{b}{13} \)[/tex]:

The correct equations are:
- [tex]\(\tan(22.6^\circ) = \frac{a}{13}\)[/tex]
- [tex]\(\tan(22.6^\circ) = \frac{13}{a}\)[/tex]
- [tex]\(\tan(22.6^\circ) = \frac{a}{12}\)[/tex]
- [tex]\(\tan(22.6^\circ) = \frac{12}{a}\)[/tex]

Given the confirmed values from the tangent calculation:
- [tex]\( 31.230, 5.411, 28.828, 4.995 \)[/tex]

Thus, all the given options are mathematically consistent. The correct usage depends on what configuration of the right triangle's sides you view.