Answer:
9-(x+y)
Step-by-step explanation:
9 would be before x and y for the equation bc it states 9 first
when it says x and y, it means that you add so x+y but you have to put in parentheses bc you have to find the value of x and y first
so lets say, for example, 9 decreased by x and y, x=3 and y=2
so the equation is 9-(x+y)
so then the new equation would be 9-(3+2)
so then 3+2 is 5 so you subtract 5 from 9 which would be 4
hope this helps