SOLUTION: Determine whether the graphs of the equations are perpendicular. 5x-8y=3, 5y-8x=2. Are the graphs of the given equations perpendicular?

Algebra ->  Graphs -> SOLUTION: Determine whether the graphs of the equations are perpendicular. 5x-8y=3, 5y-8x=2. Are the graphs of the given equations perpendicular?      Log On


   

Question 285162: Determine whether the graphs of the equations are perpendicular. 5x-8y=3, 5y-8x=2. Are the graphs of the given equations perpendicular?
Answer by eggsarecool(46) About Me  (Show Source):
You can put this solution on YOUR website!
To do this you need to solve both equations for y, once you have done this you will be able to see the slopes and that will tell you if they are perpendicular.
So 5x-8y=3 add 8y to both sides.
5x=8y%2B3 subtract 3 from both sides.
5x-3=8y And divide through by 8.
%285%2F8%29%2Ax-3%2F8=y So the slope is m=5%2F8 that comes from the number attached to the x.
For the next equation.
5y-8x=2 Add 8x to both sides.
5y=8x%2B2 And divide through by 8.
y=%288%2F5%29%2Ax%2B2%2F5
So the slope is m=8%2F5
The definition for two lines to be perpendicular is that the slope of one must be the negative reciprocal of the slope of the other. The negative reciprocal of 5%2F8 is -8%2F5 and we only got 8%2F5 so they are not perpendicular.