The green value is derived from equation 1. It's just taking equation 1 and rearranging it. So putting the green equation for x back into equation 1 won't do anything useful.
Yes. The red value is the expression from x derived from eqn 2, so the next step is to substitute this into eqn 1 and that gives you an equation to find y.
Although I would approach this in a slightly different way ...
Ohk. Sir . The thing is this. When we put red value in equation 1. We get the value of determinant as shown in the textbook. Now , if we put green value in equation 1. Then , can I do that since that step would give different variable as the value of determinant
You got the same equation, but you've multiplied by -1 on both sides. Just multiply both sides of your equation by -1 and you'll see it's the same as the book.
Sir, in my textbook it is written that if we bring a positively charged body near an electroscope which is already positively charged then due to induction a negative charge appears on the top part of rod of electroscope hence the net positive charge between the two gold foils increase and they diverge even more.
I am having the question that instead of the top part of rod getting negatively induced, why doesn’t the charged object gets polarized instead of the rod and then we get a wrong conclusion using the book’s method.
Both objects get polarised. Suppose we have a ball with a positive charge and the electroscope rod has a positive charge, then when I bring the ball near the top of the electroscope the positive charges repel.
So on the ball the positive charge flows to the side farthest from the electroscope, and on the electroscope the charge flows to the part farthest from the ball.
and @JohnRennie if we again have a smaller and bigger positive charge but now the smaller charge is an insulator, then the bigger charge will be polarized ?
@RishiNandhaVanchi I know you can . Btw , there is a site online where there is an online tutorial by Amit Trivedi ( The musician who made the beat for andhadhun and many other great songs) is going to teach how he did it.