Answer:
The difference between 19 and 8 is 11.
Step-by-step explanation:
Given:
The difference between a number and 8 is 11
Find the number.
Solution:
Let the unknown number be 
The difference between the unknown number can be written as:

We are given that the difference =11
So we can write the equation to find
as :

Using additive property to solve for 
Adding 8 to both sides to isolate
on one side.

∴ 
∴ The unknown number = 19
question a is 80
question b 20 (is what I could find but not completely sure)
Answer:
The attached image shows the graph for the given function.
Step-by-step explanation:
We are given the following function in the question:

We have to graph the given function.
Properties of the given function are:
- It is an exponential function of the form

- Here, a = 2, b = -1
- The y-intercept of the given function is (0,0.5)
- There is no x-intercept.
- The domain of the given function is all real numbers.
- The range of given function is

The attached image shows the graph for the given function.