Assertion: parabola's focus | /r/HasProperty | \displaystyle f=(f_{1},f_{2
Facets:
Source sentences:
text: If the focus is F = ( f 1 , f 2 ) {\displaystyle F=(f_{1},f_{2})} , and the directrix a x + b y + c = 0 {\displaystyle ax+by+c=0} , then one obtains the equation