Answer
$\sin A=\frac{5\sqrt 7}{20}$
$\cos A=\frac{3}{4}$
$\tan A=\frac{\sqrt 7}{3}$
Work Step by Step
Using the Pythagorean theorem to find the other side of the right triangle:
$a^2+b^2=c^2$
$a^2+15^2=20^2$
$a=5\sqrt 7$
$\sin A=\frac{5\sqrt 7}{20}$
$\cos A=\frac{15}{20}=\frac{3}{4}$
$\tan A=\frac{5\sqrt 7}{15}=\frac{\sqrt 7}{3}$
