Question

In the triangle below, which is equivalent to sinA?

Answer 1

we have that

sin A=BC/AC

and
cos C=BC/AC

therefore
sin A= cos C

the answer is cos C

Answer 2

1. By definition, you have:

Sin(α)=Opposite/Hypotenuse

2. Then, SinA is:

SinA=BC/AC

A is the angle in the vertice "A".
BC is the opposite leg to the the angle A.
AC is the hypotenuse of the triangle.

3. By definition, you have:

Cosα=Adjacent/Hypotenuse

4. Then, CosC is:

CosC=BC/AC

C is the angle at the vertice "C".
BC is the adjacent leg to the angle C.
AC is the hypotenuse.

5. Therefore, the answer is the last option:

The equivalent to SinA is CosC