Question 980907
Hi there,
First work out gradient:
Gradient = y2 - y1/x2 - x1
Utilising (4,-2) and (6, -8)
-8 -(-2)/6 - 4
-8 + 2/6 - 4
-6/2
= -3
If two lines are perpendicular to one another
then their gradients multiply together to give -1
m1 x m2 = -1
So, -3 x m2 = - 1
m2 = 1/3
Next use line equation:
y - b = m(x - a)
Utilising m = 1/3 and (12, -5)
y -(-5) = 1/3(x - 12)
y + 5 = 1/3(x - 12)
y + 5 = 1/3x - 4
y = 1/3x -4 - 5
y = 1/3x - 9
or
3y = x - 27
Hope this helps:-)