Honestly this problem you can use both x and y but x tends to be the easier one to use and i would use the first equation because it is easier to solve because all the numbers are even.<span />
Answer:
I'm not 100 percent sure but but part a is
0 0
6 18
12 36
and then part b is letter A
Step-by-step explanation:
hope this helps
Ordered pairs that work for this direct variation are (4, 3), (8, 6) and (12, 9).
In order to find these, we must first find the value of the direct variation coefficient. We can do that using the base equation y = kx and then by plugging in to find k.
y = kx
12 = k(16)
3/4 = k
Now that we have k, we can model the equation as y = 3/4x. We can also find any number of ordered pairs by using the x value and finding the y value. All of the above answers work.
10 times 90 is 900, and divided by -19 is -900/19.
Answer:
the question is incomplete, so I looked for a similar one:
<em>After the release of radioactive material into the atmosphere from a nuclear power plant, the hay was contaminated by iodine 131 ( half-life, 8 days). If it is all right to feed the hay to cows when 10% of the iodine 131 remains, how long did the farmers need to wait to use this hay? </em>
iodine's half life (we are given x, we need to find b):
0.5A₀ = A₀eᵇˣ
x = 8 days
we eliminate A₀ from both sides
0.5 = eᵇ⁸
ln 0.5 = ln eᵇ⁸
-0.69315 = b8
b = -0.69315 / 8 = -0.08664
since the farmers need to wait until only 10% of the iodine remains (we already calculated b, now we need to find x):
0.1A₀ = A₀eᵇˣ
0.1 = eᵇˣ
ln 0.1 = bx
where b = -0.08664
x = ln 0.1 / -0.08664 = -2.302585 / -0.08664 = 26.58 days
