Substituting in the values we know gives: \({hypotenuse} = \frac {5} {cos~25\circ}\) We obtain the value of cos 25° by using the cos button on the calculator, followed by 25. This gives us ...

Image caption, To write cos⁻¹ on a scientific calculator, press 'shift' and ... 12 cm should be labelled as hypotenuse (\(h\)) because it is the longest side and is opposite the right angle.