a)
[tex]\sqrt{2}x+3=4\\\sqrt{2}x=4-3\\\sqrt{2}x=1\\x=\frac{\sqrt{2}}{2}[/tex]
b)
[tex]\frac{x-\sqrt{5}}{3}=\frac{x+\sqrt{5}}{4}\\\left(x-\sqrt{5}\right)\cdot \:4=3\left(x+\sqrt{5}\right)\\4x-4\sqrt{5}=3x+3\sqrt{5}\\4x=3x+7\sqrt{5}\\4x-3x=7\sqrt{5}\\x=7\sqrt{5}[/tex]
