What is the slope of a line parallel to #3x+4y=12#?

1 Answer
Sep 18, 2014

In this problem we must first find the slope of the given line. Also note that parallel lines have the same slope.

We have 2 options:

1) Manipulate this equation from standard form to slope intercept form, #y=mx+b#, where #m# is the slope.

2) The slope can be found using the following expression, #-A/B#, when the equation is standard form.

OPTION 1:

#3x+4y=12#

#4y=12-3x#

#(4y)/4=12/4-(3x)/4#

#y=3-(3x)/4#

#y=-3/4x+3 -> slope = -3/4#

OPTION 2:

#Ax+By=C#

#3x+4y=12#

#slope=-A/B=-3/4#

A line parallel to #3x+4y=12# must have a slope of #-3/4#.