how do i find the equation of a line, when given only the y-intercept?

Question

anonymous · Answer

Well, y intercept is when x = 0. The equation of a line is y=mx+c where M is the gradient.

anonymous · Answer

I have a line that crosses the y axis at (-1) and I need to find the equation and I'm just not really sure how to do it?

anonymous · Answer

Do you have any other information..Do you have another point on the line? Or just the yintercept as  (0, -1)

anonymous · Answer

thats all the information i have

anonymous · Answer

Damn, so no slope? Well  then from memory you can't fully solve the equation.

Substitute in your y intercept coordinate, (0, -1) into the equation, and solve for C

y=mx +c
-1 = m(0) + c
c = -1

Therefore y=mx -1

Sorry I don't know how else you can solve the equation unless given more information.

anonymous · Answer

okay thanks anyway! :))