Hello!
To find the slope of the given equation, we would need to convert this equation from standard form into slope-intercept form. Our goal, is to get the variable y, on one side of the equation.
Remember that slope-intercept form is written as y = mx + b. In this form, m is the slope and b is the y-intercept.
2x + 4y = 12 (subtract 2x from both sides)
4y = 12 - 2x (divide both sides by 4)
y = 12/4 - 2/4x → y = -1/2x + 3
Therefore, the slope of this equation is -1/2, which is the final choice listed.