Answer: r=1/2
Step-by-step explanation:
We have the equation:

We know two points and we will use them to calculate the parameters a and b.
The point (0,3) will let us know a, as b^0=1.

Now, we use the point (2, 108/25) to calcualte b:
![\begin{gathered} y=3\cdot b^x \\ \frac{108}{25}=3\cdot b^2 \\ 3\cdot b^2=\frac{108}{25} \\ b^2=\frac{108}{25\cdot3}=\frac{108}{3}\cdot\frac{1}{25}=\frac{36}{25} \\ b=\sqrt[]{\frac{36}{25}} \\ b=\frac{\sqrt[]{36}}{\sqrt[]{25}} \\ b=\frac{6}{5} \end{gathered}](https://tex.z-dn.net/?f=%5Cbegin%7Bgathered%7D%20y%3D3%5Ccdot%20b%5Ex%20%5C%5C%20%5Cfrac%7B108%7D%7B25%7D%3D3%5Ccdot%20b%5E2%20%5C%5C%203%5Ccdot%20b%5E2%3D%5Cfrac%7B108%7D%7B25%7D%20%5C%5C%20b%5E2%3D%5Cfrac%7B108%7D%7B25%5Ccdot3%7D%3D%5Cfrac%7B108%7D%7B3%7D%5Ccdot%5Cfrac%7B1%7D%7B25%7D%3D%5Cfrac%7B36%7D%7B25%7D%20%5C%5C%20b%3D%5Csqrt%5B%5D%7B%5Cfrac%7B36%7D%7B25%7D%7D%20%5C%5C%20b%3D%5Cfrac%7B%5Csqrt%5B%5D%7B36%7D%7D%7B%5Csqrt%5B%5D%7B25%7D%7D%20%5C%5C%20b%3D%5Cfrac%7B6%7D%7B5%7D%20%5Cend%7Bgathered%7D)
Then, we can write the equation as:
Using the given information we found that the equation of the parabola is:
y = (-4/9)*(x - 3)^2 + 5
And its graph is below.
<h3>
How to get the equation of the parabola?</h3>
For a parabola with vertex (h, k), the equation is:
y = a*(x - h)^2 + k
Here the vertex is (3, 5), so the equation is:
y = a*(x - 3)^2 + 5
And the y-intercept is y = 1, this means that:
1 = a*(0 - 3)^2 + 5
1 = a*9 + 5
1 - 5 = a*9
-4/9 = a
So the parabola is:
y = (-4/9)*(x - 3)^2 + 5
And its graph is below.
If you want to learn more about parabolas, you can read:
brainly.com/question/1480401
Answer:
3/6 or 1/2
Step-by-step explanation:
If there is 1 green, 2 yellow, and 3 red marbles in the bag then there are 6 marbles total. She can only pull out 3 red ones seeming there are only 3 in the bag. Therefor the probability of her choosing a red marble is 3/6 or reduced to 1/2