Answer:
1 seconds after being thrown, the stone reaches its max height
Step-by-step explanation:
The parabolic (quadratic) equation is:

Lets expand this in the form
, so we have:

We can say the values of a,b, and c, now to be:
a = -5
b = 10
c = 40
The number of seconds at which the max would occur is given by the point, x, at:

We know a and b, let's find the seconds, x,

Hence,
1 seconds after being thrown, the stone reach its max height
The number is 'n'.
Five times the number is 5n .
Nine more than that is 5n + 9 .
Rewriting the question, the given lengths that were cut from the board were 30 3/4 inches, 12 1/4 inches, and 16 1/4 inches. To obtain the remaining length of the board, all of the measurements cut are to be added and subtracted from 72 inches. This is shown below:
30 3/4 + 12 1/4 + 16 1/4 = 237/4 = 59.25 inches.
Remaining length of board = 72 - 59.25 = 12.75 inches.
Therefore, there will be 12.75 inches remaining of the board.
Answer:
b is the answer by solomon