Answer: (12, -9)
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Step-by-step explanation:
Let point S be at the location (x, y)
The x coordinates of T and S are 0 and x in that order.
Add them up and divide in half: (0+x)/2 = x/2
Set this equal to the x coordinate of the midpoint (6) and solve for x.
x/2 = 6
x = 2*6
x = 12
Point S has an x coordinate of 12.
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Follow a similar idea for the y coordinates.
The y coordinates of T and S are 3 and y in that order.
Add and divide in half: (3+y)/2
Set that equal to -3 since its the y coordinate of the midpoint.
Solve for y.
(3+y)/2 = -3
3+y = 2*(-3)
3+y = -6
y = -6-3
y = -9 is the y coordinate of point S
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Therefore, point S will be located at (x,y) = (12, -9)
Visual confirmation is shown below. Another way to verify is to use the midpoint formula on T = (0,3) and S = (12, -9) and you should get the midpoint M = (6, -3).