Answer:


Step-by-step explanation:
Given

Solving (a): Write as inverse function

Represent a(d) as y

Swap positions of d and y

Make y the subject


Replace y with a'(d)

Prove that a(d) and a'(d) are inverse functions
and 
To do this, we prove that:

Solving for 

Substitute
for d in 




Solving for: 

Substitute 5d - 3 for d in 

Add fractions



Hence:

Answer:
8/21
Step-by-step explanation:
1- 2/7 - 1/3 = 21/21 - 6/21 - 7/21 = 8/21
Answer:
<u>15%</u> percent of the bill was her tip.
Step-by-step explanation:
Given:
Audrey gave a $0.90 tip to a waitress for serving a meal costing $6.00.
Now, to find the percent of the bill was her tip.
The bill was = $6.00.
The tip she gave = $0.90.
Now, to get the percent of the bill was her tip:




Therefore, 15% percent of the bill was her tip.