Answer:
d) 4 + 7 - 2
Step-by-step explanation:
7 + 2 - 4 = 5
2 + 7 - 4 = 5
7 - 4 + 2 = 5
4 + 7 - 2 = 9
40x - 2 because you combine like terms so it's 40x and then combine 8 and -10
Answer:

Step-by-step explanation:
Given the exponential decay function 
When
then

so the initial amount is 
The exponential decay function
has the decay factor 
In your case, the eexponential decay factor is 
-6x+10 would be ur answer :)