ashakil3 wrote:

Bunel, can you please help explain the answer step by step.

I don't understand the following:

Using definitions of lines on xy-plane we get

Y 1 =X∗ba

for Y2 we got this equation: (X−c)/(b−c) =Y/a =>Y2 =a∗X/(b−c) −c/(b−c)

Thank you.

The standard equation of a line in x-y plane passing through points (a,b) and (c,d) :

\(\frac{y-b}{x-a} = \frac{d-b}{c-a}\).

Equation of line Y1 is created from the above equation of a line but now passing through the origin (0,0), substitute either (a,b) or (c,d) as (0,0) and you get (assuming (c,d) = (0,0))

\(\frac{y-b}{x-a} = \frac{d-b}{c-a}\) ---> \(\frac{y-b}{x-a} = \frac{0-b}{0-a}\) ---> \(\frac{y-b}{x-a} = \frac{b}{a}\)

---> After rearranging the terms, you get, \(y = x* (b/a)\)

For Y2, the OP has used the standard equation of a line (mentioned above).

Hope this helps.