Glencoe Math: Course 3, Volume 2
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Glencoe Math: Course 3, Volume 2 View details
3. Rotations
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Exercise 2 Page 479

Start by rotating a point by using a protractor to measure the angle.

Graph:

The quadrilateral ABCD, with vertices A(-3,-4), B(-1,-1), C(2,-2), and D(3,-4), is illustrated on a coordinate plane. Additionally, the image A'B'C'D' is shown, resulting from a 90-degree clockwise rotation about vertex A.

Coordinates: A'(-3,-4), B'(0,-6), C'(-1,-9), D'(-3,-10)

Practice makes perfect
Let's start by plotting the given vertices A(- 3,- 4), B(- 1,- 1), C(2,- 2), and D(3,- 4). Then we will connect them with line segments to draw the quadrilateral.
quadrilateral
We will now draw the image of ABCD after a 90^(∘) clockwise rotation about vertex A. For simplicity, let's start by rotating only one point. We will use vertex D. To do so, we will use a protractor to draw a ray that makes a 90^(∘) angle with AD at A.
The quadrilateral ABCD, defined by vertices A(-3,-4), B(-1,-1), C(2,-2), and D(3,-4), is depicted on a coordinate plane. Using an inverted protractor centered at point A, a ray is drawn perpendicular to side AD.

On this ray, we will mark a point D' so that AD' is the same length as AD. This is the image of D after the rotation.

The quadrilateral ABCD, with vertices A(-3,-4), B(-1,-1), C(2,-2), and D(3,-4), is depicted on a coordinate plane. A ray perpendicular to side AD passes through the point D'(-3, 10), and the segments AD and AD' are of equal length.
Next, we will repeat the same process for vertices B and C to find B' and C'. Since A is the point at which the quadrilateral is rotated, A' will be in the same position as A. The coordinates of the images of the vertices are A'(-3,-4), B'(0,-6), C'(-1,-9), and D'(-3,-10).
images
Finally, we will connect A', B', C', and D' to draw the image of ABCD.
image

Extra

Visualizing the Rotation
Let's rotate ABCD 90^(∘) clockwise about A so that we can see how it is mapped onto A'B'C'D'.
rotate