4. Choose the expression that matches the following statement: three times the difference of two times a number and 7 taken from 8 of a number.
a) 2x+21
b) 2x - 21
c) -2x - 21
d) -2x - 7

Sample response: if the graph passes the horizontaline test, then the function is one to one. functions that are one to one have inverses that a therefore, the inverse is a hinction compare your response to the sample response above. what did you include in your explanation? a reference to the horizontal-line test d a statement that the function is one-to-one the conclusion that the inverse is a function done