The answer is 2.2108
Solution:
first equation:
h = -0.2d² + 2.25d-d + 6h = 21.77
2nd equation:-d + 6h = 21.77d = 6h - 21.77
Then substitute:h = -0.2(6h - 21.77)² + 2.25(6h - 21.77)h = 3.9968
Answer:d = 2.2108
The parabola will show the vertex in the format: y-k = (x-h)^2, where the vertex point
lies at (h, k).

let's first put it in "y =" standard format:

Since we cannot get a perfect square out of this, we complete the square: a=1, b=2, c=3
(b/2)^2 = (2/2)^2 = 1, so

So there's +2 leftover, since 3-1=2; so:

Now we'll subtract the 2 from both sides to show our vertex:

where our vertex (h, k) is at (-1, 2)
Answer:
The correct option is;
b. Stem and leaf plot
Step-by-step explanation:
A stem-and-leaf plot shows the data shape and the densities of the different classes in a graphical form such that the information in the data such as the data characteristics are self displayed by the data numbers arranged in the stem-and-leaf plot. The stem-and-leaf plot keeps the raw numerical data, in the form they were obtained and by their arrangement, outliers are easily spotted.