Evaluate f(x) = x2 + 3x − 4 when x = 4:

f(x)=24

Step-by-step explanation:

Replace x in the function with the value 4.

f(4)= (4)^2 + 3(4) - 4  

16 + 12 -4

28 - 4

F(x)= 24

the answer is 0.3175 hope that you ^w^

also you might actually want to put this picture up if you want people to solve it luckily i remember this question

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.