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A partir de qual atividade o homem relacionava-se com o tempo durante o tempo medieval? 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? Problem involving math induction! 1. Prove for every integer p, p^2 + 3p + 8 is even.? What is 4 x 6? Problem involving math induction! If m and n are distinct real numbers, prove that (m+2)^2 = (n+2)^2 if and only if x+y=-4?