



 
Hi Jesse. I presume you meant to write y = 2x + 3. If the equation of a line is written in the form
then m is the slope so the first line has a slope of 2. Parallel lines have the same slope and perpendicular lines have negative reciprocal slopes. That is, if Hence a line perpendicular to your first line has an equation of the form
Since you know that this line passes through the point (3,4), you know that when x = 3 then y = 4. So you can put these values into the last equation to find the value of b.
Solve for b and you have all the pieces you need to write the equation of the perpendicular line. Stephen and Penny  


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