posted by Lilly on .
Write an equation in a standard form of the line that passes through (3,1) and has a y-intercept of-2 .
My book does not have problems like this so PLEASE help me!!!!!!!!!
given the y-intercept of -2 implies you have a second point (0,-2)
so the slope is (-2-1)/(0-3) = -3/-3 = 1
You now have the slope and the y-intercept.
Can you take it from here ?
from the information so far we would have
y = x - 2
or x - y = 2
You can always check if your equation is correct by subbing in the given points.
notice for your equation and using (3,1)
we would get
3+1 = 2 ??
How would you get a positive 2 though?
I had better put my glasses on.
I read your equation as x+y = 2, didn't notice the - sign in front.
thats ok, so would it be 4 ?
I now got -3x+y=-2
no, I thought you understood when I told you it was x-y = 2.
Let's try it again:
(3,1) and (0,-2)
slope = (-2-1)/(0-3) = 1
then using y = mx + b
we have y = (1)x - 2
or -x + y = -2
x - y = 2
ok thanks, sorry!