Iam not sure how to even start this problem or how to write it in equation form.

first part = $54,000, second part = $12,000, third part = $10,000

Explanation:

             Amount Invested        Rate              Interest

Part 1             x                            0.08              0.08x

Part 2            y                            0.06              0.06y

Part 3           z                           0.09             0.09z

TOTAL       76,000                     ******              5,940

Interest:

0.08x + 0.06y + 0.09z = 5940

0.36y + 0.06y + 0.09(76,000 - 5.5y) = 5940

       0.42y       +        6840 - 0.495y   = 5940

                                  6840 - 0.075y   = 5940

                                            - 0.075y   = -900

                                               =

                                                       y   = 12,000

x = 4.5y  

x = 4.5(12,000)

x = 54,000

             Amount Invested        Rate              Interest

Part 1           54,000                  0.08              0.08(54,000) =  4,320

Part 2           12,000                   0.06              0.06(12,000) =     720

Part 3          10,000                   0.09             0.09(10,000) =     900  

TOTAL         76,000                  ******                                          5,940

step-by-step explanation:

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.