Answer is
-1/3 slope
X intercept is 12
Y intercept is 4
Graph is attached
Step by step
Slope is rise over run
-4 rise over 12 run = -4/12 simplified to -1/3
X intercept
Substitute 0 for y and solve
1.5x + 4.5y = 18
1.5x + (4.5)(0) = 18
1.5x = 18
x = 18/1.5
x = 12
Substitute 0 for x and solve
1.5x + 4.5y = 18
(1.5)(0) + 4.5y = 18
4.5y = 18
y = 18/4.5
y = 4