Answer: 180 degrees rotation, center (1.5, -0.5)
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Step-by-step explanation:
Notice how point (1,-1) on triangle A moves to (-2,0) and then that rotates to (2,0)
Form a line segment from (1,-1) to (2,0) to show the beginning and end states. The equation of the line through these two points is y = x-2
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Similarly, the point (1,-4) moves to (-2,-3) after applying the translation vector, then it rotates to (2,3). Draw a line through (1,-4) and (2,3). The equation of this line is y = 7x-11
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We have this system of equations
Equate the right hand sides and solve for x
7x-11 = x-2
7x-x = -2+11
6x = 9
x = 9/6
x = 3/2
x = 1.5
which leads to
y = x-2 = 1.5-2 = -0.5
or
y = 7x-11 = 7(1.5)-11 = 10.5-11 = -0.5
Either way, x = 1.5 leads to y = -0.5
We get the ordered pair (x,y) = (1.5, -0.5)
This is the center of rotation when rotating figure A to have it match up with triangle C (the triangle in the upper right quadrant)
Notice in the diagram below point D is that center of rotation. Also, notice that if we use the distance formula, you should find that
AD = A''D
BD = B''D
CD = C''D