If you have MathType 6.7d or later installed, you can use it to include mathematical expressions and equations in your document. (If you don’t have MathType, you can enter mathematical expressions using the Pages equation dialog.)
Click where you want the equation to appear.
Choose Insert > Equation (from the Insert menu at the top of your screen).
Type or paste your equation in the field provided.
See MathType Help for instructions on using the MathType tools.
To save your equation, click the File menu at the top of your screen, choose “Close and Return to Pages,” then click Yes in the window that appears.
The equation appears at the insertion point in your document. To edit the equation, double-click it to open MathType again.
You can change the look of the equation, move it, or delete it just as you can other images in your document.