The standard form of a line is an easy way to solve for the properties of a line, such as slope and the intercepts. Take a line with the equation in standard form,
Ax + By = C
The slope here is given by y = -A/B.
The x-intercept here is given by (C/A, 0).
The y-intercept here is given by (0, C/B).
For this problem, the equation is 2x + 4y = 12. Thus,
slope = -2/4 = -1/2
y-intercept = (0, 12/4) = (0, 3)
