If [tex]\tan \theta=\frac{12}{5}[/tex] and [tex]\cos \theta=-\frac{5}{13}[/tex], then what is [tex]\sin \theta[/tex]?

A. 12
B. [tex]\frac{5}{13}[/tex]
C. [tex]-\frac{5}{13}[/tex]
D. [tex]\frac{12}{13}[/tex]
E. [tex]-\frac{12}{13}[/tex]



Answer :

To find [tex]\(\sin \theta\)[/tex] given that [tex]\(\tan \theta = \frac{12}{5}\)[/tex] and [tex]\(\cos \theta = -\frac{5}{13}\)[/tex], follow these steps:

1. Recall the trigonometric identity:
[tex]\[ \tan \theta = \frac{\sin \theta}{\cos \theta} \][/tex]

2. Express [tex]\(\sin \theta\)[/tex] in terms of [tex]\(\tan \theta\)[/tex] and [tex]\(\cos \theta\)[/tex]:
[tex]\[ \sin \theta = \tan \theta \cdot \cos \theta \][/tex]

3. Substitute the given values:
[tex]\[ \sin \theta = \left( \frac{12}{5} \right) \cdot \left( -\frac{5}{13} \right) \][/tex]

4. Simplify the expression:
[tex]\[ \sin \theta = \frac{12 \cdot -5}{5 \cdot 13} = \frac{-60}{65} \][/tex]

5. Simplify the fraction:
[tex]\[ \sin \theta = -\frac{60}{65} = -\frac{12}{13} \][/tex]

Thus, [tex]\(\sin \theta = -\frac{12}{13}\)[/tex].

Now, let's match this result to the given options:

- A. [tex]\(12\)[/tex]
- B. [tex]\(\frac{5}{13}\)[/tex]
- C. [tex]\(-\frac{5}{13}\)[/tex]
- D. [tex]\(\frac{12}{13}\)[/tex]
- E. [tex]\(-\frac{12}{13}\)[/tex]

The correct answer is indeed [tex]\(\boxed{-\frac{12}{13}}\)[/tex], which corresponds to option E.