Discover Questions

If 2x^2+6>7x,prove that |4x-7|>1? When x=0 does it have a y-intercept when it goes through both the x-axis and y-axis? How can space be filled with Photons if photons don't have a volume? What mass of Al2O3 is produced when 81g of Al undergoes complete combustion (with workings please)? For what values of x is (x-2)(x-3)(x-4)(x-5) < 8?