A rock is launched from a cannon. After 1 second, the rock is 243 feet in the air; after 2 seconds, it is 452 feet in the air. Using the quadratic function, find the height, in feet, of the rock after 5 seconds in the air
I've seen a similar problem to it yesterday, and I got confused lol ^_^"
What is the angle at which it is launched?
doesn't say.
a+b = 243 a = 243 - b 4a +2b = 452 4(243-b) +2b = 452 892 -4b + 2b = 452 892 -452 = 2b 440/2 = b b = 220 -------------- a = 243-220 = 23 23x^2 +220x = y -------------------- 23 + 220 = 243 checks 23(4) + 220(2) = 452 92 + 440 = 30 ok.....whatd I do wrog..hard to type in the dark :)
assume it is launched straight up. say its initial acceleration is a. distance is ut+1/2at^2
initial speed is 0. so d = 1/2 at^2
its a simple quad equation, not physics....but that might be a shot :)
(0,0) (1,243) (2,452)
since it is launched straight up in the air, the gravity is acting against the rock. so s = 1/2(a-32.17)t^2
1a + 1b = 243 b = 243-a 4a + 2b = 452 4a + 2(243-a) = 452 4a +486 -2a = 452 2a = 452 - 486 2a = -34 a = -17 by that
oh okay, then you should follow amistre 64's procedure.
b = 243 --17 b = 260 -17x^2 +260x = y -17(4) + 260(2) = 452 -68 + 520 = 452 right? someone tell me its right lol
452 is the height of the rock at 2 seconds.
amistre64 can u please help me
the numbers are working yay!!...plug in a 5
plug in a 5 where?
-17(25) +260(5) = ?
that's what i thought. i just tried it. i got 875
-425 + 1300= 875....me too :)
correct! one more to go! let's hope i pass it this time! i've only missed one outta 4. on to the 5th question. thanks amistre64!
i wrote you a quad program today, but left my flash drive at the college lol
thanks though!
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