Question 72505
3X-4Y=12
-4Y=-3X+12
Y=-3X/-4+12/-4
Y=3X/4-3 THUS THE SLOPE OF THIS LINE IS 3/4. 
THUS A PERPENDICULAR LINE HAS A SLOPE THAT IS A NEGATIVE RECIPRICAL OF 3/4 WHICH IS -4/3
NOW FIND THE X INTERCEPT FOR 
4X-13=3Y
3Y=4X-13
Y=4X/3-13/3 TO FIND THE X INTERCEPT OF THIS LINE WE SET Y=0 THUS:
0=4X/3-13/3
4X/3=13/3
X=13/3*3/4
X=13/4 NOW WE NEED TO FIND THE Y INTERCEPT (b)
0=-4/3*13/4+b
0=-13/3+b
b=13/3 THUS THE EQUATION IS
Y=-4X/3+13/3
{{{ graph( 300, 300, -6, 5, -6, 5, y = 3x/4 -3, y = -4x/3 -13/3 ) }}} (graph 300x300 pixels, x from -6 to 5, y from -6 to 5, of TWO functions y = 3x/4 -3 and y = -4x/3 -13/3).