writing the equation in the form y = mx +b
[tex]\begin{gathered} 8x+3y=10 \\ 8x-8x+3y=-8x+10 \\ \frac{3y}{3}=\frac{-8x}{3}+\frac{10}{3} \\ y=-\frac{8}{3}x+\frac{10}{3} \end{gathered}[/tex]slope is -8/3 and If you multiply the slopes of two perpendicular lines, we get -1, therefore
[tex]-\frac{8}{3}\times\frac{3}{8}=-1[/tex]value the slope of a line perpendicular to line FG is 3/8
