Question

Transform x+y+1=0 into coordinate form

Answer 1

Formula used:

Normal form of straight line is

x\:cos\:\alpha+y\:sin\:\alpha=p

Given line is x+y+1=0

It can be written as

- x - y =1

divide both sides by \sqrt{(-1)^2+(-1)^2}=\sqrt{2}, we get

x(\frac{-1}{\sqrt{2}})+y(\frac{-1}{\sqrt{2}})=\frac{1}{\sqrt{2}}\\\\x.cos(\frac{5\pi}{4})+y.sin(\frac{5\pi}{4})=\frac{1}{\sqrt{2}}