# Are the two lines 15x-3y = 12 and y = 5x + 7 parallel or perpendicular?

Jun 2, 2015

$15 x - 3 y = 12$ and be written as
$\textcolor{w h i t e}{\text{XXXXX}}$$y = 5 x - 4$
which is a line with slope $5$

$y = 5 x + 7$
also has a slope of $5$

Therefore the two lines are parallel.

The above assumes recognition of the slope y-intercept form for a line:
$\textcolor{w h i t e}{\text{XXXXX}}$$y = m x + b$ which has a slope of $m$ and a y-intercept of $b$.