Answer:
Step 5
Step-by-step explanation:
The mistake is in step 5.
The previous step was

The order operations, PEDMAS, must be applied:
We have Addition and Division here,
Using PEDMAS, we must divide first to get:

We can now add to get:

Therefore the mistake occurred at step 5
Answer:
the third one
Step-by-step explanation:
its easy
Only numbers possible would be five and zero
Answer:
f(x)=-
x+9
Step-by-step explanation:
Use the slope formula and slope intercept formula form y=mx + b to find the equation