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Quadrilateral ABCD with vertices A(-3,3), B(8,8), C(6,2), D(0,0) is shown. You want to reflect quadrilateral ABCD in the horizontal line that passes through the midpoint of segment BC. Graph the line of reflection and the image after the reflection.

User Aamol
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To reflect quadrilateral ABCD across the horizontal line through the midpoint of BC, find the midpoint, use its y-coordinate to define the line of reflection, then reflect each point across this line. The reflected quadrilateral has vertices at A'(-3,7), B'(8,8), C'(6,2), D'(0,10), and the line of reflection is y = 5.

To reflect quadrilateral ABCD in the horizontal line that passes through the midpoint of segment BC, we first need to find the midpoint of BC. The coordinates of B and C are B(8,8) and C(6,2), respectively.

The midpoint, M, of a segment with endpoints (x1, y1) and (x2, y2) is given by M = ((x1 + x2)/2, (y1 + y2)/2). Hence, the midpoint of BC is M = ((8 + 6)/2, (8 + 2)/2) = (7, 5).

This midpoint will be a point on the line of reflection. Since the line of reflection is horizontal and passes through M, its equation is y = 5. To find the image of each vertex after reflection, we take each y-coordinate and find its distance to the line y = 5, then move that vertex the same distance on the other side of the line.

Reflecting point A(-3,3): The distance from A to the line of reflection is |3 - 5| = 2. So, the image of A, which we'll call A', will be at (-3,5 + 2) = (-3,7).

Since points B and C are on the line of reflection, their images will be the same as their original positions. So, B' is at (8,8) and C' is at (6,2).

Reflecting point D(0,0): The distance from D to the line of reflection is |0 - 5| = 5. So, the image of D, which we'll call D', will be at (0,5 + 5) = (0,10).

The reflected quadrilateral A'B'C'D' has vertices at A'(-3,7), B'(8,8), C'(6,2), and D'(0,10). The line of reflection is y = 5, and this geometric transformation results in a symmetrical image across the horizontal line.

Below is the attached graph

Quadrilateral ABCD with vertices A(-3,3), B(8,8), C(6,2), D(0,0) is shown. You want-example-1
User John Pertoft
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