Answer: (0,c) which is the third answer choice
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Step-by-step explanation:
Note how the point (a,0) mirrors over the y axis to land on (-a,0)
A similar action will happen as we go from te point (b,c) to point W (-b, c), due to this figure being isosoceles.
The x coordinate changes from positive to negative. The y coordinate stays the same.
The point Z is the midpoint of the upper segment which spans from (-b,c) to (b,c)
Apply the midpoint formula to find where Z is located.
Add up the x coordinates and divide by 2: x = (-b+b)/2 = 0/2 = 0
Add up the y coordinates and divide by 2: y = (c+c)/2 = 2c/2 = c
So the midpoint is located at (x,y) = (0, c) which is where point Z is located as well.
Side note: it might help to replace the letters a, b and c with actual values, just so the problem is more concrete.