The perpendicular from the origin to the line y = mx + c meets it at the point (-1, 2). Find the values of m and c.
Given: perpendicular from the origin and meets at the point (-1, 2)
Explanation:
The given line is y = mx + c which can be written as mx –y + c = 0 … (1)
The slope of the line perpendicular to y = mx + c is 
So, the equation of the line with slope  and passing through the origin is
 and passing through the origin is

x + my = 0 … (2)
Solving eq(1) and eq(2) by cross multiplication, we get


Thus, the point of intersection of the perpendicular from the origin to the line y = mx + c is 
It is given that the perpendicular from the origin to the line y = mx + c meets it at the point (-1, 2)
 and
 and 
⇒ m2 + 1 = mc and m2 + 1
⇒ mc 
⇒ m 
Now, substituting the value of m in m2 + 1 = mc, we get

⇒ c 
Hence, m  and c
 and c 