Technically this is not necessarily true for all. A function has each input mapped to one output, therefore there can be two inputs that have the same output. However, when inverted, the input will have two outputs, which is not a function. For example with (1,3) (2,3) (3,4) (4,5) this is a function but switched (3,1) (3,2) ! Two inputs have the same output, which is not a function!
Answer:
9x+9y
Step-by-step explanation:
9(x+9y
9x+9y
solution
9x+9y