Question

Determine the equation of the line with slope 3 that passes through the point M(1, 2).

3x + y = 1
3x − y = −1
3x - y = 1
x − 3y = −1

Answer 1

Explanation:

We are given the slope along with an (x, y) coordinate with which to write the equation. You could use this info in the slope-intercept form and solve for b, or you could use this info in the point-slope form and solve it for y. Trust me when I tell you that either one will get you the correct equation. Promise! I used the point-slope form, just because. ; )

y - 2 = 3(x - 1) and

y - 2 = 3x - 3 and

y = 3x - 1 OR in standard form, we will put the x and y terms on the same side of the equals sign, separated from the constant:

-3x + y = -1. But if we get picky and do not like to lead with negatives, we could change ALL the signs to their opposites (which is the same as multiplying the whole thing by a -1) to get

3x - y = 1 which is the third choice down.