3. Solve for x2=81 C. 10

9

Step-by-step explanation:

9 x 9 = 81

x = ±9

Step-by-step explanation:

x^2 = 81

Take the square root of each side

sqrt(x^2 ) = ±sqrt(81)

x = ±9

1)is not similar since corresponding sides are not in the same ratio

2)are similar since corresponding sides are in the same ratio and corresponding angles are equal

hope it will

#faazmessi

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.