Find equations of the lines through the given point parallel to the given line and perpendicular to the given line.
point (7/8, 3/4)
line 5x + 3y = 0

Equation of a line passing through point (x1, y1) with slope m is given by y - y1 = m(x - x1)
For perpendicular lines, the slope of the required line is given by -1 divided by the slope of the given line.
5x + 3y = 0
3y = -5x
y = -5/3x
slope of the given line is -5/3.
Thus, the slope of the required line = -1/(-5/3) = 3/5

y - 3/4 = 3/5(x - 7/8)
5(y - 3/4) = 3(x - 7/8)
5y - 15/4 = 3x - 21/8
40y - 30 = 24x - 21
24x - 40y = -30 + 21 = -9
24x - 40y = 9.