Question

Find the angle measure that makes the statement true.
Sin 25° = Cos ____ °

Answer 1

We know that sin(x) = cos(90°-x). In that sense, we know that:

sin(25°) = cos(90°-25°) = cos(65°)

If you put both values in a calculator, we get that:

sin(25°) = 0.4226

cos(65°) = 0.4226

Therefore: Sin 25° = Cos 65°