y=mx+c
1) FIND M
Perpendicular lines formula
m1 x m2 = -1
- gradient of the lines multiplied together equals to -1
Substitute
m1 x m2 = -1
12 x m2 = -1
m2 = -1/12
m2 = -0.083
2) FIND C
Now we know m, y and x, so we can find c.
(x,y) -> (10,-5)
y=mx+c
-5=-0.083*10+c
-5=0.83+c
-5-0.83=c
c=-5.83
So the equation would be
y=-0.08x+5.83
