Question

Determine the equation of the line passing through the points (−1,1) and (1,7).

Write the line in standard form Ax+By=C.

Answer 1

`3x - y = -4`

Explanation:

To make things easier, let's first find the equation in slope-intercept form (
`y = mx + b` where m is the slope and b is the y-intercept.

1. Find the slope:

`(7 - 1)/(1 - (-1)) = (6)/(2) = 3`

2. Find the y-intercept by plugging in (-1,1) into the equation
`y = 3x + b`

`1 = 3(-1) + b`

so
`b` = 4

3. Therefore the equation of the line in slope-intercept form is
`y = 3x + 4`

4. To convert slope-intercept form into standard form, let's move the 3x over to the other side and divide by -1 to get rid of the negative.

Our result is
`3x - y = -4`.

Hope this helps :)