Question

A line with a slope of -2 crosses the y-axis at (0, 3). The equation of the line is

Answer 1

y - y1 = m(x - x1)
y - 3 = -2(x - 0)
y = -2x + 3

Answer 2

The slope-intercept form of the equation of a line is

y = mx + b,

where

m = slope and b = y-intercept.

The point (0, 3) is the y-intercept, so b = 3.
The slope is -2, so m = -2.

y = mx + b

y = -2x + 3