Answer:
[tex]sina =\frac{5}{13}[/tex] is the answer.
Step-by-step explanation:
It is given that in a right angle triangle angle B is a right angle triangle and [tex]cosa=\frac{12}{13}=\frac{Base}{hypotenuse}[/tex]
Now we see in the figure attached Base(adjacent side) is 12 and hypotenuse is 13.
We have to find sina.
since [tex]sina = \frac{height}{hypotenuse}[/tex]
We will find the length of hypotenuse with the help of Pythagoras theorem.
BC = √(13²-12²) = √(169-144) = √25 = 5
Now from the given triangle [tex]sina =\frac{BC}{AC}=\frac{5}{13}[/tex]
The correct option is [tex]sina =\frac{5}{13}[/tex]
