The inverse of the function is 
Explanation:
To find the inverse of the equation
, we need to interchange the variables x and y for the variables y and x.
Thus, the equation becomes

Now, we shall find the value of y.
Now, adding 8 to both sides of the equation, we have,

Interchanging the sides,

Dividing by 2 on both sides,

Taking square root on both sides,

Thus, the inverse of the function is 
Answer: In the beginning he was given 27 sweets.
Step-by-step explanation: The most logical thing to do is to solve it backwards, that is, from what he had at the end of the third day up till the beginning of the first day.
On the third day he ate one-third and had 8 sweets left over. To determine how many he started with on the third day, let the total on day three be called a. If one-third of a is eaten, then the left over which is two-thirds is 8. That is;
8/a = 2/3
By cross multiplication we now have
8 x 3 = 2a
24/2 = a
a = 12
Let the number of sweets he had on day two be called b. If he ate one-third of b and he had 12 left over, then the two-thirds left over is 12 and we now have;
12/b = 2/3
By cross multiplication we now have
12 x 3 = 2b
36 = 2b
36/2 = b
b = 18
Let the number of sweets he had on day one be called x. If he ate one-third of x and he had 18 left over, then the two-thirds left over is 18, and we now have;
18/x = 2/3
By cross multiplication we now have
18 x 3 = 2x
54 = 2x
x = 27
Therefore Tim was given 27 sweets at the beginning.
If a pack of paper costs 3.75 including tax, and there is a $20 budget, then the equation to find out the answer would be 3.75p is greater or equal to $20. So the answer would be B. 3.75 would be multiplied by the tax and then applied up to $20.