Question 1047532
In case you don't know how to take values directly from an equation to determine slope  (for a line), try this:  Find ANY two points of the line.  Determine the ratio of vertical change to horizontal change.  I would not really want to do that with this equation, but, if you want, you can find the axis intercepts, and use THEM to find slope.


{{{x=0}}},
{{{-7y=-19-4*x}}}
{{{y=19/7+4*x}}}
{{{y=19/7+4*0}}}
{{{y=19/7}}}
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This intercept is  (0, 19/7).


{{{y=0}}},
{{{4x=19+7y}}}
{{{x=19/4+7y/4}}}
{{{x=19/4+7*0/4}}}
This intercept is  ( 19/4, 0)



WHAT IS THE SLOPE OF THE TWO POINTS?
{{{(19/7-0)/(0-19/4)}}}---------to find ratio of vertical change to horizontal change;
{{{(19/7)/(-19/4)}}}

{{{-(19/7)*(4/19)}}}

{{{highlight(-4/7)}}}-------------THE SLOPE



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HOW TO FIND SLOPE FROM THE STANDARD FORM EQUATION OF LINE


Your given equation is almost in standard form.
{{{Ax+By=C}}}
{{{By=-Ax+C}}}
{{{y=-(A/B)x+C/B}}}----------This is now in SLOPE-INTERCEPT form, and the slope is shown directly here as  {{{-A/B}}}.


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NOTE:  Teacher probably showed how but too early for you to fully understand.  Review lecture notes and review the book's discussion.