Aline segment is drawn from (+6, +4) to (+9, +4) on a coordinate grid.

which explains one way that the length of this line segment can be determined?

a.
add 9 + 6.

b.
add 6 + 6.

c.
subtract 9 – 6.

d.
subtract 6 – 6.

Letter c. add 9-6 explains one way that the length of this line segment can be determined. In order to verify this for yourself, you can plot these two point on a Cartesian coordinate plane and manually measure the length of the line. Mathematically, the length of a line may be calculated by the distance formula given as: sqrt[(x2-x1)^2+(y2-y1)^2]