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6. rotate the line segment (overline{ab}) (90^circ) clockwise around th…

Question

  1. rotate the line segment (overline{ab}) (90^circ) clockwise around the point ((1, -1))

Explanation:

Step1: Find coordinates of A and B

From the grid, assume each grid is 1 unit. Let's find coordinates:

  • Point A: Let's see, x = -5, y = 3 (since from x=-5, y=3). Wait, maybe better to check the grid. Wait, the origin is (0,0), so A is at (-5, 3), B is at (-3, 3)? Wait, no, maybe I misread. Wait, the x-axis: -5, 0, 5. So A is at (-5, 3), B is at (-3, 3)? Wait, no, the line segment AB is horizontal? Wait, the problem says rotate around (1, -1). Let's confirm coordinates. Let's assume A is (-5, 3), B is (-3, 3).

Step2: Translate the points so that the center of rotation (1, -1) becomes the origin

To translate, we subtract (1, -1) from each point.
For point A: \( A' = A - (1, -1) = (-5 - 1, 3 - (-1)) = (-6, 4) \)
For point B: \( B' = B - (1, -1) = (-3 - 1, 3 - (-1)) = (-4, 4) \)

Step3: Rotate the translated points 90° clockwise

The rotation formula for 90° clockwise around origin is \( (x, y) \to (y, -x) \)
For \( A'(-6, 4) \): \( A'' = (4, -(-6)) = (4, 6) \)
For \( B'(-4, 4) \): \( B'' = (4, -(-4)) = (4, 4) \)

Step4: Translate back by adding (1, -1) to the rotated points

For \( A''(4, 6) \): \( A''' = (4 + 1, 6 + (-1)) = (5, 5) \)
For \( B''(4, 4) \): \( B''' = (4 + 1, 4 + (-1)) = (5, 3) \)

Wait, maybe my initial coordinates were wrong. Let's recheck the grid. Let's see, the x-axis: -5, 0, 5. The y-axis: -5, 0, 5. Let's find A and B correctly. Let's look at the grid: A is at (-5, 3), B is at (-3, 3). Wait, but when we rotate around (1, -1), let's do the steps again.

Alternative approach: The vector from center (1, -1) to A: A - center = (-5 - 1, 3 - (-1)) = (-6, 4). Rotating this vector 90° clockwise: (4, 6) (since (x,y)→(y, -x), so (-6,4)→(4, 6)). Then new A is center + (4,6) = (1 + 4, -1 + 6) = (5,5). Similarly, vector from center to B: (-3 -1, 3 - (-1)) = (-4,4). Rotate 90° clockwise: (4,4). New B is (1 + 4, -1 + 4) = (5,3). So the rotated segment AB has endpoints (5,5) and (5,3), which is a vertical segment.

Answer:

The rotated line segment \(\overline{AB}\) has endpoints at \((5, 5)\) and \((5, 3)\) (or the segment connecting these two points).