Answer:
85 students are in the ninth grade
Step-by-step explanation:
17 + 23 = 40
200/40 = 5
17 *5 = 85
no. f-1 does not equal to f.
it's Exponential .......
-6y^3+7y^2-2
(-2y^3+2y^2-9)+(-4y^3+5y^2+7)
-2y^3-4y^3+2y^2+5y^2-9+7