Question

Write the point-slope form of an equation of the line through the points (-1, 4) and (-2, 2).

Answer 1

`y-4=2(x+1)`

Explanation:

Point-slope form is equal to

`y-y_1=m(x-x_1)`

where y and y1 are the known y coordinates of two points on the line, and x and x1 are the known x coordinates of two points on the line. All we need now is m, which is the slope:

`4-2=m(-1-(-2))`

We can simplify negative one minus negative two as positive 1.

`4-2=m(1)`

4 minus 2 is 2, so m times 1 is 2. That means m is 2.

Now, we have the slope, so we can convert to point-slope form using one of the two points. Let's use (-1, 4). We can plug those values in for x1 and y1:

`y-4=2(x+1)`

Answer 2

Point-slope form: y-4=2(x+1)

Slope intercept form: y=2x+6

I hope this helps!