Question

Write the equation of a line with the given information in point-slope form, through point (-2,3) and slope -1/2

Answer 1

Do you know the point-slope formula?

Answer 2

Uh.. y-y1=m(x-x1)?

Answer 3

Correct!

Answer 4

So m is the slope, and (x1,y1) is a point on the line.

Answer 5

In this case you have m = -1/2, and (x1,y1) = (-2,3)

Answer 6

So plug in those values into your formula

Answer 7

Im confused. What am i plugging in?

Answer 8

The m and the (x1,y1) you were given.

Answer 9

They said the slope (m) is -1/2, So put that in for m.
They said a point (x1,y1) on the line was (-2,3) so plug in those numbers for x1 and y1.

Answer 10

Does that make sense?

Answer 11

Yes. so now i have y-3=-1/2(x+2)?

Answer 12

Yes indeed. except I'd like to see the parens around the fraction just to be totally clear:
y-3=(-1/2)(x+2)
or with the editor:
\[y-3 =- \frac{1}{2}(x+2)\]

Answer 13

Then if you need to have it in slope-intercept form you just solve for the y.

Answer 14

Well.. i dont know what i need it in. What is the equation of a line? Did i already do that?

Answer 15

This is _an_ equation for the line.

Answer 16

There are a lot of other equations that make this same line.

Answer 17

Well.. then i will just keep it as is, and if tis wrong, too bad. (:

Answer 18

it's not wrong. It's definitely an equation for that line. It just might not be the equation the teacher is looking for. But in that case they should be more specific.