Compare the benefits and disadvantages to the different alternative energy technologies.

The alternative energy technologies all provide renewable sources of energy. They all help reduce the environmental impact of energy use. The use of solar, hydropower, wind, and geothermal energy is dependent upon the availability of those resources. Solar energy is not as efficient in some locations as it is in others. This is true of wind, geothermal, and hydropower as well. Biofuels can be used to fuel cars and are less dependent on location than other alternative energy technologies, but they have limitations associated with them as well.

From Quizlet

try using substitution:

x + y - 6 = x - y. (i'm not giving you the exact answer). since 0 = x - y, then sub 0 in the equation with x - y. combine your like terms, and then use inverse operations, and you'll have your answer.

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