Explanation:
Given points (4 , -4) and ( 1, 2)
First calculating slope (m)
=( y2 - y1) /( x2 -x1)
= ( 2 + 4) / (1-4)
= 6/ -3
= -2
Now
The equation in point slope form
y - y1 = m ( x - x1)
y + 4 = -2 ( x - 4)
y + 4 = -2x + 8
2x + y - 8 + 4 = 0
2x + y -4 = 0 which is the required equation