Answer:
Let R = radius of big circle
r=radius of small circle
A1=Area of small circle
A2=Area of big circle
R=9r
A1=50cm^2
A1=pi*r*2
A2=pi*R^2
A2=pi*(9r)^2
A2=81*pi*r^2
A2=81*A1
A2=4050cm^2
Hence the big circle has area of 4050cm^2
Step-by-step explanation:
Answer:
Step-by-step explanation:
8r + 9 + 7r + 6 = 90
15r + 15 = 90
15r = 75
r = 5
8(5) + 9 = 40 + 9 = 49
7(5) + 6 = 35 + 6 = 41
Answer:

Step-by-step explanation:
From the given exponential graph, the y-intercept is (0,10).
The only exponential function that, has this intercept is

Because when x=0, we obtain:

Simplify:

We call:

as the set of <span>the first 51 consecutive odd positive integers, so:
</span>

Where:





<span>and so on.
In mathematics, a sequence of numbers, such that the difference between two consecutive terms is constant, is called Arithmetic Progression, so:
3-1 = 2
5-3 = 2
7-5 = 2
9-7 = 2 and so on.
Then, the common difference is 2, thus:
</span>

<span>
Then:
</span>

<span>
So, we need to find the sum of the members of the finite series, which is called arithmetic series:
There is a formula for arithmetic series, namely:
</span>

<span>
Therefore, we need to find:
</span>
Given that

, then:

Thus:

Lastly: