Find the equation of a straight line which cuts an intercept of length 4 units in the negative direction of y-axis and is parallel to the line joining the points (3,−2) and (1,4)
3x + y + 4 = 0
An equation of the straight line whose slope is m which makes on intercepts c on the y-axis is
y=mx+c
Slope of required line is same as the slope of the parallel line
Slope parallel line m = y2−y1x2−x1
=4+21−3
= 6−2
= −3
Intercept c=−4
Equation of the straight line
y=mx+c
y=−3x−4
3x+y+4=0