Question

2x^2 + 4 = 40 (abc )

Answer 1

`2x^2+4=40\ \ \ \ \ |-4\\\\2x^2=36\ \ \ \ |:2\\\\x^2=18\to x=\pm√(18)\\\\x=\pm√(9\cdot2)\\\\x=\pm\sqrt9\cdot\sqrt2\\\\x=-3\sqrt2\ \vee\ x=3\sqrt2`