Finding a missing side
The question
cm
Find the opposite, angle 65°
How it works.
opposite ÷ hypotenuse=sine
sin 65° = x ÷ 5
x=4.5
- 01
The angle is 65°. You know the hypotenuse (5) and you want the opposite (x). Sine is opposite over hypotenuse, so use sine.
- 02
Write it with the numbers: sin 65° = x ÷ 5.
- 03
x is on top, so multiply both sides by 5: x = 5 × sin 65°. On a calculator (in degrees), sin 65° ≈ 0.9063, so x ≈ 4.5.