## Algebra 1: Common Core (15th Edition)

a) Find the slope of each line by writing their equation in slope-intercept form: $4x-3y=9$ $3y=4x-9$ $y=\frac{4}{3}x-3$ The slope of the graph of $y=\frac{4}{3}x-3$ is $\frac{4}{3}$ The slope of the graph of $y=\frac{3}{4}x+7$ is $\frac{3}{4}$ The slopes are not the same, so the lines cannot be parallel. Multiply the slopes: $\frac{4}{3}\times\frac{3}{4}=1$. The slopes are neither opposite reciprocals nor perpendicular. b) Find the slope of each line by writing their equation in slope-intercept form. $6y=-x+6$ $y=\frac{-1}{6}x+1$ The slope of the graph of $y=\frac{-1}{6}x+1$ is $\frac{-1}{6}$ The slope of the graph of $y=-\frac{1}{6}x+6$ is $\frac{-1}{6}$ The slopes are the same, so the lines will be parallel.