Let line 1 be the graph of 5x+8y=-9. Line 2 is perpendicular to line 1 and passes through the point (10,-10). If line 2 is the graph of the equation y=mx+b, then find m+b.
5x + 8y = -9
Slope of this line = -5/8
Slope of a perp. line = 8/5
So using (10 , -10) we have
y = (8/5)(x - 10 ) - 10
y = (8/5)x - 16 - 10
y = (8/5)x - 26
m = 8/5 b = -26
m + b = 8/5 - 26 = 8/5 - 130/5 = - 122 / 5
