Line pb is a line segment on a number line. It has endpoints at -2 and 12. What is the coordinate of its midpoint.

My answer would be the total length pf pb is 14 units so the midpoint would be 7.

2 answers

the length is correct. But the midpoint is -2+7 = 5.

5 = -2+7 = 12-7
if three points a,b and c are collinear and b is between a and c then ab+bc=ac