Apple Pages V7.1 introduced significantly improved support for equations. If you choose to Insert an Equation, you are given this window.
where you can paste LaTex or MathML commands. FX Equation and FX Chem are the perfect tools for generating the appropriate commands. Just change FX Equation to Target Simple LaTex.
Type your equation in FX Equation and press the green tick/check mark button. The appropriate LaTex commands will be placed on the clipboard, ready to be pasted into Pages' equation box.