How to find the vertex of a parabola in standard form

In the first triangle 80+20+p=180 (since sum of all angles of a triangle is 180)so p= 80also in second triangle 55+45+q=180 (since sum of all angles of a triangle is 180)so q=80so we can conclude that p=80 degrees q=80 degrees so p=q=80 degreeshence option b is correct

Cbecause they are equal so that means it is the same on both sides? ! hope this

A=l×wa=(8x+6) (13x+11)a=104x➋+166x+66