Xis the midpoint of ab. b has coordinates (12,−7), and x has coordinates (3,−1). identify the coordinates of a.

Count the distance in x and y separately from B to X

12 -> 3 = 9 (subtracted) , -7 -> -1 = 6 (added).

X is midpnt, so if we go from B to X, we must go from X to get A.

subtract another 9 from the x value, and add another 6 to the y value of X

That gives us -6, 5, which are the coordinates of A.

3. (5x + 1) - (-10x + 6)

simplify the answer choice. combine like terms. remember to distribute the negative to the terms inside the second parenthesis. also remember that two negatives = one positive, and one of each sign = negative.

- (-10x + 6) = + 10x - 6

simplify. combine like terms:

5x + 1 + 10x - 6

5x + 10x + 1 - 6

15x - 5

∴ it is your answer

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