Q of Sallen key low pass filter
When you compare the general form of the transfer function with the function derived from the circuit (given in your contribution) you can identify the pole frequency wp and the pole-Q (Qp).
The expression which appears as a factor at s² is 1/wp².
And the factor appearing at the s-element is 1/(wpQp).
From this comparison you can derive the formulas for Wp and Qp.