What is (3+x)(4+x) in standard form ?

x^2+7x+12

Step-by-step explanation:

multiply the parenthesis  3 x 4 + 3x + 4x + x + x

12 + 3x + 4x + x^2

12 + 7x + x^2

then order them like the answer

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.

a)(x-2)^2+(y-1)^2=9

step-by-step explanation:

(picture explains)