9. the inverse of an ordered pair on a graph is its reflection across the line y = x. always true sometimes true never true 10. the inverse of a linear function is a linear function. always true sometimes true never true 11. the inverse of a line with positive slope is a line with negative slope. always true sometimes true never true 12. the inverse of a line with a slope greater than 1 is a line with slope less than 1. always true sometimes true never true 13. the inverse of the inverse of point (x, y) is the original point. always true sometimes true never true 14. the line y = k, where k is a constant, has an inverse. always true sometimes true never true