Question

in exercises 15 and 16, find the angle of rotation that maps a onto a. (see example 4.)
15.
image of two intersecting lines k and m with angle 55° between them, and triangles labeled a, a, a

Explanation:

Step1: Identify angle between lines k and m

The given angle between lines k and m is $55^\circ$.

Step2: Calculate rotation angle

The angle of rotation mapping A to $A''$ is twice the angle between the intersecting lines (k and m). So, $2 \times 55^\circ = 110^\circ$.

Answer:

$110^\circ$