## College Algebra 7th Edition

(a) $3$ (b) $3$ (c) $-\dfrac{1}{3}$
RECALL: (1) The slope-intercept form of a line's equation is $y=mx+b$ where m = slope and b = y-intercept. (2) Parallel lines have equal slopes.. (3) Perpendicular lines have slopes that are negative reciprocals of each other (product is -1). (a) Thus, the slope of the line whose equation is given is $3$. (b) Lines parallel to the given line have a slope of $3$. (3) Lines perpendicular to the given line have a slope of $-\dfrac{1}{3}$.