Question

what does the notation r90°,d(dab) mean? 270° 90° 180° over the y - axis over the x - axis around b around a around d around the origin counter - clockwise clockwise rotation reflection

Explanation:

Step1: Analyze rotation - notation

The notation \(R_{90^{\circ},O}\) represents a rotation. Here, \(R\) stands for rotation, \(90^{\circ}\) is the angle of rotation, and \(O\) (in general, when the center is not otherwise specified and just an angle - rotation is given, it is around the origin) is the center of rotation. Counter - clockwise is the default direction for positive angle rotations in a coordinate plane.

Answer:

Counter - clockwise, \(90^{\circ}\), Around the origin, Rotation