The source of heat for a (an) system is electricity

Electric Heating systems use electricity as a source of heat.

Explanation:

Each heater consists of an electric resistor, which the heating element in it. The process involved is Joule Heating. It is the phenomenon in which, passage of electric current produces heat. Heat is generated when the electrons from the current and the positive ions of the conductor start interaction.

The presence of voltage difference makes an electric fields, which in turn accelerates the charges present in the conductors. When they collide with ions of conductor, heat gets generated, and emitted out, which we use for heating purposes.

because it says use -2,0,and 2 for x, we can plug those numbers into the equation. y/4=3/4(-2)+2   y/4= -1 1/2 +2 now to get x by itself, we can multiply each side by 4. y=-6+8 which equals y=2 when x=-2. now you can do the same thing with 0 and 2 as x. you get y=8 when x=0 and y=14 when x=2.

x   |   y

-2 |   2

0   |   8

2   |   14