Open the compass it is more than half of the distance between a and b, and scribes arcs of the same radius centered at a and b. call the two points where these two arcs meet c and d. Draw the line between c and d. CD it is the perpendicular bisector of the line segment AB. call the point where CD intersects AB and E
Combine the terms. Note that: one positive and one negative sign results in a negative sign.
Simplify: 5 + (-4) = 5 - 4 = 1
1 + (-7) = 1 - 7 = -6
-6 + 2 = -4
-4 is your answer
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