Step-by-step explanation:

Answer:
B.

Step-by-step explanation:
5x - 3 = y then 5x = y + 3 then x = (y + 3)/5
then the inverse function of f is : (x+3)/5
Answer:
2 13/20
Step-by-step explanation:
53/20
Simplify
2 13/20
Answer:
50400
Step-by-step explanation:You just need to plug it in 3 where x is.Once you done that you need to multiply 8400x2 because we multiply from left to right this will equal 16800 then finally multiply that by 3 and you get 50400 or you could multiply first 2x3 and get 6 then 8400x6 which still equals the same thing.
Answer: the number of four point questions in the test is 10.
the number of five point questions in the test 8
Step-by-step explanation:
Let x represent the number of four point questions in the test.
Let y represent the number of five point questions in the test.
There are 18 questions on the test. It means that
x + y = 18
Each question is worth either four or five points. The total is 80 points. This means that
4x + 5y = 80 - - - - - - - - - - - - - -1
Substituting x = 18 - y into equation 1, it becomes
4(18 - y) + 5y = 80
72 - 4y + 5y = 80
- 4y + 5y = 80 - 72
y = 8
x = 18 - y = 18 - 8
x = 10