Question 278609
9x-8y=7
9y-8x=4
.
9x-8y=7
-8y=-9x+7
y=9x/8 - 7/8
.
9y-8x=4
9y=8x+4
y=8x/9 + 4/9
.
No, because in order to be perpendicular m (slope)  has to be the negative reciprocal of the slope of the other equation in the slope intercept form and these are not.
.
Ed
.
{{{graph(500,500,-10,10,-10,10,(9x/8)-7/8 ,(8x/9)+4/9)}}}