help in don’t know what to do

Answer:
Slope: -1
y-intercept: (0, 9)
Step-by-step explanation:
The slope is -1 because -1x is the same as -x and the slope is the number before x. The y-intercept is (0, 9) because the y-intercept is what y is when x is 0 so y = -1(0) + 9 which equals 9.