<span>Highest point = 1406.25
Number of seconds = 9.375
We've been given the quadratic equation y = -16t^2 + 300t which describes a parabola. Since a parabola is a symmetric curve, the highest value will have a t value midway between its roots. So using the quadratic formula with A = -16, B = 300, C = 0. We get the roots of t = 0, and t = 18.75. The midpoint will be (0 + 18.75)/2 = 9.375
So let's calculate the height at t = 9.375.
y = -16t^2 + 300t
y = -16(9.375)^2 + 300(9.375)
y = -16(87.890625) + 300(9.375)
y = -1406.25 + 2812.5
y = 1406.25
So the highest point will be 1406.25 after 9.375 seconds.
Let's verify that. I'll use the value of (9.375 + e) for the time and substitute that into the height equation and see what I get.'
y = -16t^2 + 300t
y = -16(9.375 + e)^2 + 300(9.375 + e)
y = -16(87.890625 + 18.75e + e^2) + 300(9.375 + e)
y = -1406.25 - 300e - 16e^2 + 2812.5 + 300e
y = 1406.25 - 16e^2
Notice that the only term with e is -16e^2. Any non-zero value for e will cause that term to be negative and reduce the total value of the equation. Therefore any time value other than 9.375 will result in a lower height of the cannon ball. So 9.375 is the correct time and 1406.25 is the correct height.</span>
394.6÷9=43.84 your answer is this perhaps
Using the Polynomial Division: Divide 5
−2
+2x−4 using long polynomial division.
Answer to the Polynomial Division: 
A graphing calculator working the quadratic regression problem for these three points gives the equation as
y = 2x² +7x -5
Answer:
x1, x2 = 4.74 , -2.74
Step-by-step explanation:
To find the roots of a quadratic function we have to use the bhaskara formula
ax^2 + bx + c
x^2 - 2x - 13
a = 1 b = -2 c = -13
x1 = (-b + √ b^2 - 4ac)/2a
x2 =(-b - √ b^2 - 4ac)/2a
x1 = (2 + √ (2^2 - 4 * 1 * (-13)))/2 * 1
x1 = (2 + √ (4 + 52)) / 2
x1 = (2 + √ 56 ) / 2
x1 = (2 + 7.48) / 2
x1 = 9.48 / 2
x1 = 4.74
x2 = (2 - √ (2^2 - 4 * 1 * (-13)))/2 * 1
x2 = (2 - √ (4 + 52)) / 2
x2 = (2 - √ 56 ) / 2
x2 = (2 - 7.48) / 2
x2 = -5.48 / 2
x2 = -2.74