Question 86118
Given line is -3x + 2y = 15

==> 2y = 3x + 15
==> y = 3/2 x + 15/2

This is of the form y = mx + c where m is the slope.

So slope of this line is 3/2

Therefore the slope of the perpendicular line is -1/(3/2){as product of the slopes             of perpendicular ines is -1 always]

                                                = -2/3

Thus the slope of the line perpendicular to the given line is -2/3