Step-by-step explanation:
I assume that "ground" is at 0 ft height. which is in an actual scenario not airways the case.
y = -16x² + 64x + 89
shows us that the tower is 89 ft tall (the result for x = 0, at the start).
anyway, if the original assumption is correct, then we need to solve
0 = -16x² + 64x + 89
the general solution for such a quadratic equation is
x = (-b ± sqrt(b² - 4ac))/)2a)
in our case
a = -16
b = 64
c = 89
x = (-64 ± sqrt(64² - 4×-16×89))/(2×-16) =
= (-64 ± sqrt(4096 + 5696))/-32 =
= (-64 ± sqrt(9792))/-32
x1 = (-64 + 98.95453501...)/-32 = -1.092329219... s
x2 = (-64 - 98.95453501...)/-32 = 5.092329219... s
the negative solution for time is but useful here (it would be the time calculated back to ground at the start).
so, x2 is our solution.
the rocket hits the ground after about 5.09 seconds.
Answer:
One way to factor equation is to find the zeros. Its obvious that x=-1 is solution for this. So one factor is (x+1)
the next factor should include 2x at first (because we have 2x^2 in the equation which can not be made any other way)
Let's suppose the factor is (x+1)(2x+b)
Since we do not know what is b open the brackets 2x^2+bx+2x+b. If this is equal to 2x^2+5x+3 then b=3. We are left with (x+1)(2x+3)=2(x+1)(x+3/2)
Would go for other shorter solutions, but they require some deeper understanding like Horner's scheme,Fermat's Theorem or even deeper which I assume You will not understand)
Answer:
5.2 Minutes, or 5 minutes and 12 seconds
Step-by-step explanation:
You can solve this problem by working backward. Since our number gets smaller by a 1/10 or 0.1, in order to work backward we must multiply 3.60 by 10/9, since one tenth has been taken away already. When we do this, we get 4.0. When we add 1.2 minutes to that, we get a final answer of 5.2 minutes, or 5 minutes and 12 seconds.
22° you just subtract the numbers.
The answer to 685 divided by 49 = 13.979