A quadratic equation is in the form of ax²+bx+c. The time at which the height of the ball is 16 feets is 0.717 seconds and 1.221 seconds.
<h3>What is a quadratic equation?</h3>
A quadratic equation is an equation whose leading coefficient is of second degree also the equation has only one unknown while it has 3 unknown numbers. It is written in the form of ax²+bx+c.
The complete question is:
A ball is thrown from an initial height of 2 feet with an initial upward velocity of 31 ft/s. The ball's height h (in feet) after 7 seconds is given by the following, h=2+31t-16t². Find all values of t for which the ball's height is 16 feet. Round your answer(s) to the nearest hundredth.
The time at which the height of the ball is 16 feet can be found by,
h = 2 + 31t - 16t²
16 = 2 + 31t - 16t²
16 - 2 - 31t + 16t² = 0
16t² - 31t + 14 = 0

t = 0.717 , 1.221
Hence, the time at which the height of the ball is 16 feets is 0.717 seconds and 1.221 seconds.
Learn more about Quadratic Equations:
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I believe the answer is B) positive
Answer:
Some answers to the reducing fraction sheet
Q14 = 4/5 because divide 12 and 15 by 3
Q15=can't be reduced because 11 is a prime number so it can't be divided by anything
Q17=can't be reduced because 17 is a prime number
Q18=can't be reduced because 13 is a prime number
Q19=38/9 because 114 and 27 would be divided by 3
Q20= -1/1 because you would divide both 14,529 by itself would equal to - 1/1
I can only help you with this sheet I can't help you with the other one hope this was helpful! :)
Answer:
G). 1.2x + 7.92 -3.3x = 41
-2.1x=33.08
x = 33.08/-2.1
x = - 15.752
H). 3x/2 + 9/5 = 12
Multiply through by 10
15x + 18 =120
15x =120-18
15x = 102
x =102/15
x=34/5
I). 5 = 9/4 - r/3
Multiply through by 12
60= 27 - 4r
60 - 27 = -4r
33 = - 4r
r = -33/4
J). 2(x - 2) = 12
2x - 4 = 12
2x = 16
x = 16/2
x = 8