Find an equation of the line with x-intercept 2 and y-intercept -3.

Question

braydonlevi99 · Answer

Which type of equation do you want to use?

rissa · Answer

y=mx+b i assume

braydonlevi99 · Answer

Yes, so you know that the x-intercept is 2. What does the x-intercept usually represent?

rissa · Answer

when the line intercepts at x (2,0)

braydonlevi99 · Answer

X-Intercept can also mean the slope. And the y-intercept is usually your starting point. Now, plug in what you know.

mathstudent55 · Answer

The x-intercept is where the line crosses the x-axis. It has nothing to do with slope.

braydonlevi99 · Answer

What do you think the answer would be, Rissa?

mathstudent55 · Answer

If you are given 2 points on a line, you can find the equation of the line.
The x-intercept and the y-intercept are two points on the given line.
That is enough information to find the equation of the line.

mathstudent55 · Answer

@rissa
The x-intercept is where the line crosses the x-axis.
If the x-intercept is 2, what are the coordinates, (x, y), of the x-intercept?

rissa · Answer

(2,0) (0,-3)

rissa · Answer

than i find the slope ?

rissa · Answer

and plug in?

braydonlevi99 · Answer

|dw:1471801946526:dw|

braydonlevi99 · Answer

What is the slope of that line?

braydonlevi99 · Answer

I'm pretty sure that this wold be your answer:
$$y = \frac{ 3 }{ 2 } - 3$$

mathstudent55 · Answer

Correct.
Find the slope between the two intercepts.

mathstudent55 · Answer

$m = \dfrac{y_2 - y_1}{x_2 - x_1} = \dfrac{-3 - 0}{0 - 2} = \dfrac{-3}{-2} = \dfrac{3}{2}$

mathstudent55 · Answer

Now that you have the slope, m = 3/2, and the y-intercept, b = -2, you can use the slope-intercept form of the equation of a line which you wrote at the beginning of this post.

y = mx + b

Just substitute the values you have for m and b.

rissa · Answer

y=3/2x-3