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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? W800: How many degrees C° does w800 reach? When the pressure that a gas exerts on a sealed container changes from -atm to 1.80 atm, the temperature changes from 86.0 C to 30.0 C.? What would happen if I caught alien war ships and planes and went to Jupiter could I used to save people people lives.? If a+b+c=4, ab+ac+bc=6, and abc=3, what is 1/a + 1/b + 1/c?