Which is the correct way to evaluate f(15) for the function f(x)=2(x+3)?

start by substituting 15 for x. then, simplify to get f(15)=36.
since f(15) is not within the domain of the function, it cannot be evaluated.
since f(15) means the output value is 15, the function evaluates to f(15)=15.
start by letting 2(x+3)=15, then solve for x. when solved, the answer is x=4.5.

the first option

Step-by-step explanation:

Start by substituting 15 for x. Then, simplify to get f(15)=36.

cuz

f(x)=2(x+3)

f(15)=2(15+3)

= 2×18=36

gimme brainliest plz

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.