Question

rotate the given triangle 90° counterclockwise about the origin. 0 - 3 5 ; 0 1 2 0? ; 0

Explanation:

Step1: Matrix rotation formula

The rotation matrix for a \(90^{\circ}\) counter - clockwise rotation is \(

$$\begin{bmatrix}0&-1\\1&0\end{bmatrix}$$

\).

Step2: Apply the rotation formula

For a point \((x,y)\), after a \(90^{\circ}\) counter - clockwise rotation about the origin, it becomes \((-y,x)\).
For the point \((-3,1)\):
\(x=-3,y = 1\)
New \(x=-y=-1\)
New \(y=x=-3\)

Answer:

\(

$$\begin{bmatrix}-1\\-3\end{bmatrix}$$

\)