Question

Find an equation of the line:

through the point (2, −4) with a y-intercept of −2

Answer 1

As we're given a point on the line and the slope of the line, use the "point-slope" formula for the equation of a straight line:

y = mx + b

Here everything is known except for the slope, m. Substitute -2 fpr b, -4 for y and 2 for x:

-4 = m(2) - 2. Adding 2 to both sides of the equation, we get

-2 = 2m, and thus m = -1.

The desired equation is y = -x - 2.