Look at the opening
An angle measures how far two arms open from their shared corner. Turning the whole figure changes its direction, not its opening.
These two openings are equal. One drawing has shorter arms, but arm length does not decide the size of an angle.
Start from the same direction
These two angles are aligned: one arm of each points right from the same kind of horizontal starting line. The drawings use the same scale and equal arm lengths.
A opens 30° and B opens 70°, so A comes first from smallest to largest. Alignment turns the whole figure without changing its opening.
Compare a new pair
The angles point in different directions again. Imagine turning one arm of each to the same starting direction, then compare their openings.
Try it
Which angle has the smaller opening?
- Angle A.
- Angle B.
Show the answer
Angle B.
B opens 40°, while A opens 65°. Turn both figures to the same starting direction in your mind: B still opens less.
Enable JavaScript to answer interactively and save your place.