Answer:
The steps below show how I transformed the equation in the question into standard form, where the slope and y-intercept is clearest. The slope is -1/2 and the y-intercept is 32.
[tex]4x + 8y = 512 \\ x + 2y = 64 \\ 2y = - x + 64 \\ y = - \frac{1}{2} x + 32[/tex]
