Answer: (-1, 6)
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Step-by-step explanation:
The x coordinates of the two points are -6 and 4. They add to -6+4 = -2. Cut this in half to get -2/2 = -1.
The y coordinates of the two points are 3 and 9. They add to 3+9 = 12. Cut this in half to get 12/2 = 6.
The midpoint formula is
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In short, you add the corresponding coordinates and then divide by 2.