Question

Quadrilateral mark will be reflected across the x-axis and then rotated 90 degrees clockwise about the origin to create quadrilateral m'a'r'k'. If m is located at (-3, 7), what will be the y-coordinate of m'?

a) 3
b) -3
c) -7
d) 7

Answer 1

After reflecting point m across the x-axis and then rotating it 90 degrees clockwise about the origin, the y-coordinate of m' is 3.

Step-by-step explanation:

The original location of point m is (-3, 7). When it is reflected across the x-axis, its coordinates become (-3, -7) because a reflection over the x-axis changes the sign of the y-coordinate but leaves the x-coordinate the same.

Next, when we rotate the point 90 degrees clockwise about the origin, the x-coordinate becomes the y-coordinate, and the y-coordinate becomes the negative of the x-coordinate. Thus, from (-3, -7), the new coordinates become (7, 3).

Therefore, the y-coordinate of m' after these transformations is 3. The correct answer is (b) 3.