(W+X)² = (W+X)(W+X)
This can be expanded to;
(W+X)(W+X)= W²+WX+WX+X²
=W²+2WX+X²
Perfect square trinomial states: if (W+X)² format is placed, the first term is squared, the last is squared and the middle term is a multiplication of squareroot values of W and X multiplied by 2.
Hope I helped :)
