The range of the function f(x) = x + 5 is {7, 9}. What is the function’s domain?

Question

i need help with my mastery test 

Answer 1

y = f(x) = x + 5 = 7

 

x = 2

 

y = f(x) = x + 5 = 9

 

x = 4

 

The domain is {2, 4}