The additive inverse of a number is just the opposite of the given number. For example; 2 and the additive inverse is -2.
If we apply this to the number we are given, we get 19.57
Best of Luck!
The sketch of the parabola is attached below
We have the focus

The point

The directrix, c at

The steps to find the equation of the parabola are as follows
Step 1
Find the distance between the focus and the point P using Pythagoras. We have two coordinates;

and

.
We need the vertical and horizontal distances to find the hypotenuse (the diagram is shown in the second diagram).
The distance between the focus and point P is given by

Step 2
Find the distance between the point P to the directrix

. It is a vertical distance between y and c, expressed as

Step 3
The equation of parabola is then given as

=


⇒ substituting a, b and c


⇒Rearranging and making

the subject gives
In chess, the Endgame is where you sacrafice pawns, or in this case, minor characters in order to get a powerful piece back. You can leave some pawns in battle while regaining power pieces. The pawns sacraficed were Peter, Stephen, Bucky, Drax, T'challa. Mantis, etc. While leaving behind two pawns: Nebula, and Bruce Banner. Normally I like to think of the Hulk as a Rook, but since he's completely useless at the moment, he's a pawn. Nebula's fairly worthless, so she's a pawn. Thanos is playing with all power pieces and one pawn: Gamora. He sacraficed his pawn in order to complete his queen equivilence: the gauntlet. Now he's playing with all power pieces, while the Avenger's have sacraficed their pawns in order to get their queen: Captain Marvel, who in turn will wage war on Thanos only to find that a pawn has made it across the board and turned into the Hulk, and fights side by side the original Avengers to get the soul stone, revive Tony, who probably dies, get their friends home, welcome new friends, and kill Thanos.
Sorry about the rambling. I'm not even sure if I got to the point.