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Could someone help me with these math problems? I can't figure them out. Solve the linear equation;
x+2y=15
y=-2x+0 9x-12y=-3
-12x+16y=4? Describe how and where new crust material is made. Describe how and where old crust is destroyed.? How many molecules are in 97.8g of FeCl3? Find all of the actual roots of the polynomial: x^3 - 2x^2 + 5x + 26 = 0? An action potential can be referred as a ¨wave of depolarization¨ down the axon. Explain what you think this means.?