Question

2 - 84 determine which of the following pairs of triangles are similar. justify your answer

Explanation:

Step1: Find the third - angle of the first triangle

The sum of angles in a triangle is $180^{\circ}$. For the first triangle with angles $60^{\circ}$ and $40^{\circ}$, the third - angle is $180-(60 + 40)=80^{\circ}$.

Step2: Compare angles of the two triangles

The first triangle has angles $60^{\circ},40^{\circ},80^{\circ}$ and the second triangle has angles $60^{\circ},80^{\circ},40^{\circ}$. Since the corresponding angles of the two triangles are equal, the two triangles are similar by the AA (angle - angle) similarity criterion.

Answer:

The two triangles are similar.