Chapter 9, Problem 13MCQ

To determine

To find the image of point M after the rotation of ${90}^{\circ }$ about the origin.

Answer to Problem 13MCQ

Option A is correct.

Explanation of Solution

Given:

The followingis the figure-

  

Calculation:

To rotate a point ${90}^{\circ }$ counter clockwise about the origin, multiply the y-coordinate by $-1$ and then interchange the x-coordinate and y-coordinate. From the graph, the point $M(1,3)$ and so its image is

  $\begin{array}{l}(x,y)=(-y,x)\\ M(1,3)=M\text{'}(-3,1)\end{array}$

So, the correct answer is choice A.