Answer:
B = (7, 2)
Explanation:
B = 2M -A
B = 2(3, 4) -(-1, 6) = (2·3-(-1), 2·4-6)
B = (7, 2)
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The expression for the other end point, B, comes from the equation for the midpoint.
M = (A +B)/2
2M = A + B . . . . . multiply by 2
2M -A = B . . . . . . subtract A to get an expression for B