Write an equation in point-slope form of the line passing through the point (0,-1) that is parallel to the line y =-2x-3

Answer 1

Any two lines with the same slope (as long as they are not right on top of each other) are parallel. That means that line 2 (y = -2x -3) has the same slope as line 1 (the one we are looking for). The slope of line 2 is easy to see since the form given is the slope-intercept form (y = mx + b). The slope is just the coefficient in front of the "x" so it is "-2".

So line 1 (the one we are looking for) also has a slope of "-2" and we also know it goes through the point (0, -1). The point-slope form of a line is y - y₁ = m(x - x₁) where the point that the line goes through is (x₁, y₁). In this case, just plug in x₁ = 0 and y₁ = -1 so:

y - -1 = -2(x - 0) or y + 1 = -2x