
Given equations are:
2x - 3y + 4 = 0 .............1
3x + 4y - 5 = 0..............2
After solving it, we get
x = -1/17, y = 22/17
Suppose that person is standing at point P(-1/17, 22/17)
Again given line is 6x - 7y + 8 = 0
Slope = 6/7
Slope of perpendicular line is = -7/6
Now equation of line passing through (-1/17, 22/17) and perpendicular to 6x - 7y + 8 = 0 is
y - 22/17 = (-7/6)*(x + 1/17)
=> 6(17y - 22)/17 = (-7)*(17x + 1)/17
=> 6(17y - 22) = (-7)*(17x + 1)
=> 102y - 132 = -119x - 7
=> 119x + 102y - 132 + 7 = 0
=> 119x + 102y - 125 = 0
This is the required equation of line.