Check out the drawing below. The triangles are to scale.
- Angle A of triangle ABC is between sides AB = 3 and CA = 6
- Angle P of triangle PQR is between sides PQ = 3 and RP = 6
So far, we have two sides that are 3 units long (AB and PQ) and two sides that are 6 units long (CA and RP) when we compare the angles A and P.
The difference is that side BC = 4 is shorter than QR = 5. This is the exact reason why angle A is smaller than angle P. The smaller the opposite side gets, the smaller the angle gets, and vice versa. Think of it like a door. As the door opens further, the distance from the door handle to the door frame increases which in turn increases the angle.
