Choose the sources of heat which create metamorphic rocks?

Hot molten rock called magma and geothermal heat

Explanation: Metarmorphic Rock are formed from the break down of existing igneous and sedimentary rock as a result of the intrusion of magma and high pressure which brings about a change in the physical and chemical nature of the rock into a denser form called metarmorphic Rock. Also, it is formed as a result of geothermal heat and friction along the fault.

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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