William W. answered 09/21/19
Math and science made easy - learn from a retired engineer
For the function f(x), the expression f(5) just means plug 5 into the equation rule associated with the function. The function rule associated with f(x) in this case is 6(x-2) because f(x) = 6(x-2)
To find f(5), plug in 5 wherever you see x in the function rule so:
f(5) = 6(5-2) = 63 = 6*6*6 = 216