A ball is thrown into the air with an initial upward velocity of 46 ft/s. Its height (h) in feet after t seconds is given by the function h=-16t^2 +46t +6. After how many seconds will the ball hit the ground?
A. 3
B. 4
C. 5
D. 6
I am at this part:-16t^2 +46t +6=0
I dont know how to factor this....can someone plz help me
actually i got y’all:
b
a
a
c
d
c
c
a
I just took it and the answers only changed slightly
1.) B | (1,3)
2.) A | Maximum
3.) A | 3
4.) C | 42 feet
5.) D | 11, -11
6.) C | -7,-1
7.) C | -6,4
8.) A | 3.33 ft
There y'all go- I wouldn't have spent so long typing that if it was wrong LSDFHK good luck fellow cheaters ^^
kabutos admirer is 100% correct!
yea kabutos admirer is correct 😄👍🏼.
-16t^2 +46t +6=0
is the sameas
16 t^2 - 46 t - 6 = 0
which is
8 t^2 - 23 t - 3 = 0
now factor
the quadratic equation means
if
a x^2 + b x + c = 0
then
x = [ -b +/- sqrt (b^2 - 4 a c) ]/ (2a)
You can get it by completing the square
a x^2 + b x = -c
x^2 + (b/a) x = -c/a
x^2 + (b/a) x + (b / 2a)^2 = -c/a + (b / 2a)^2
(x+ b/2a)^2 = -c/a + (b / 2a)^2
x+ b/2a = +/- sqrt (-c/a+b^2/4a^2)
x = -b/2a +/- sqrt [ (- 4 c a + b^2 )/4 a^2 ]
= -b/2a +/- (1/2a)sqrt (b^2 - 4 a c)
= [ -b +/- sqrt(b^2 - 4ac) ] / 2a
kabutos admirer is a life saver <3
right off you can see
need
( something - 3)(something + 1)
or
(something +3 )(something -1)
so the answer?
3 seconds?
V = Vo + g*Tr = 0
46 - 32Tr = 0
Tr = 1.44 s. = Rise time.
V^2 = Vo^2 + 2g*h1 = 0
46^2 - 64h1 = 0
h1 = 33 ft. above launching point.
h = 33+6 = 39 ft. above gnd.
16Tf^2 = 39
Tf = 1.56 s. = Fall time.
Tr+Tf = 1.44 + 1.56 = 3 s. to hit gnd.
so try (t-3)( something t + 1)
Kabutos admirer really is a life saver. XD Those are still the correct answers as of today!
omg TYSM SukunaIsMyHusbando!
I've been looking up quadratic formulas and everything but oml these word problems suck </3
(the only reason i made it through the blanket in the practice one was acting like it was a riddle and not doing any math </3)
thank you soooosoo much everyone especially kabutos admirer!! have a great day everyone!! :3
SukunaIsMyHusbando is correct, I hot 8/8 thank you
Kabuto is right! Their a life saver 100% correct! ❤❤
Kabuto still 100%
@ SukunaIsMyHusbando is still correct has of 2023 lol
karaboutos is still correct as of april 28 2021
Kabutos is correct as of now
hello??? answers pleaseee
why factor? Just use the quadratic formula. It always works.
Update! I took the quiz and I got 4/8. I guess they changed the answers :/
The new ones are:
b
a
c
d
c
c
b
a
good luck guys!