What is #3x-4y=12# in slope-intercept form?

1 Answer
Sep 29, 2016

#y = 3/4x-3#

Explanation:

Slope-intercept form means we are looking for an equation of the type #y = mx+b#

Starting with #3x-4y=12#, we can add #4y# to each side, yielding
#3x-4y+4y=12+4y #
and #-4y+4y = 0#, so we are left with
#3x=12+4y#
We now subtract 12 from both sides:
#3x-12=12+4y-12#
#12-12 = 0#, leaving us with:
#3x-12 = 4y#
We now divide by 4 on both sides:
#(3x-12)/4 = (4y)/4#
We know #(4y)/4 = y#
On the left hand side, we can split #(3x-12)/4# into #(3x)/4 - 12/4#.
Simplifying, we find #3/4x - 3 = y#, which is in slope intercept form, as requested.