Answer:
D. -1/3
Explanation:
The given equation is 1.5·x + 4.5·y = 8
The slope of the graph of the equation can be found by presenting the equation in slope and intercept form, y = m·x + c,
Where;
m = The slope
c = The y-intercept
We have as follows;
1.5·x + 4.5·y = 8
4.5·y = 8 - 1.5·x
∴ y = 8/4.5 - 1.5/4.5·x = 16/9 - 1/3·x
y = 16/9 - 1/3·x
Comparing with the general form of a linear equation given in slope and intercept form, y = m·x + c, we have;
y = 16/9 - 1/3·x = -1/3·x + 16/9
Therefore;
m = -1/3
c = 16/9
Therefore, the slope of the graph = -1/3.