The cosine ratio is adjacent leg divided by the hypotenuse.
The hypotenuse in a right triangle is the longest side and it is opposite the right angle.
An adjacent leg is the side that has an endpoint that is at the vertex of the angle and the other endpoint is at the vertex of the right angle.
cos A = [tex] \frac{12}{20} = \frac{3*4}{5*4} = \frac{3}{5} [/tex]
ANSWER: [tex]cosA= \frac{3}{5} [/tex]
