In right triangle ABC with angle B = 90 degrees, we have 2 sin A = 5 cos A. What is sin A?
Note that
2 sinA = 5 cos A rearrange as
sin A / cos A = 5/2
tan A = 5/2 = y/x
r = sqrt [ x^2 + y^2 ] = sqrt [ 2^2 + 5^2 ] = sqrt (29)
sin A = y/r = 5/sqrt (29) = 5 sqrt (29) / 29
