2x+y+1=0; How do you solve these equations?

Question

2x+y+1=0; How do you solve these equations?

 

Answer 1

     2x + y + 1 = 0

This is a first degree equation with two unknown variables, x and y. They are referred to as linear equation and are typically represented in slope-intercept form, y=mx+b, where m is the slope of the line and b is the y-interecept. So you want to set the equation equal to y by isolating it to one side of the equation.

Subtract all term other than y (in this case, 2x and 1) from both sides of the equation.

      2x + y + 1 - 2x - 1 = 0 - 2x - 1 

       y = -2x - 1

Answer 2

Darren,

2x+y+1=0

A couple of comments:

If this were 2x²+x+1=0 I would say it is a quadratic equation which can be solved using the quadratic formula. But it is 2x + y not 2x² + x.

Also, a genreal rule is that if you have 0 on one side of the equation, you can move something over. In this case you could subtract 1 from both sides so you have 2x+y=-1. Or you could subtract everthing but y in order to isolate y which would be y=-2x-1.

But, without more information about either y or x, you cannot "solve" this equation as it stands.

 

If this is meant to be a line equation then you could graph it by reformulating into a line equation form y=mx+b where m is the slope and b is the y-intercept. That is essentially what we did before by making it y=-2x-1. So the slope is -2/1 and the y-intercept is -1. 

 

hope this helps, if not please add more info on the question

Chris