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The number line shows the distance in meters of two skydivers, a and b, from a third skydiver located at point x: a horizontal number line extends from negative 3 to positive 3. the point labeled as a is at negative 2.5, the point 0 is labeled as x, and the point labeled b is at 0.5. write an expression using subtraction to find the distance between skydivers a and b. show your work and solve for the distance using additive inverses.