Answer:
Step-by-step explanation:
Since area of a circle is pi.r^2
We know that diameter is 20
Radius is half of diameter
So it becomes
Pi.(d/2)^2
So pi.(40/4) is the area of this circle.
Or 40pi/4
Answer:the angles are 12 degrees, 48 degrees and 120 degrees.
Step-by-step explanation:
The sum of the angles in a triangle is 180 degrees.
The measures of the angles of XYZ are in the ratio 1:4:10. The total ratio is the sum of the proportion of each angle. It becomes
1 + 4 + 10 = 15
Therefore, the measure of the first angle would be
1/15 × 180 = 12 degrees
Therefore, the measure of the second angle would be
4/15 × 180 = 48 degrees
Therefore, the measure of the third angle would be
10/15 × 180 = 120 degrees
Answer:

Step-by-step explanation:
<u>Ratios
</u>
We are given the following relations:
![a=\sqrt{7}+\sqrt{c}\qquad \qquad[1]](https://tex.z-dn.net/?f=a%3D%5Csqrt%7B7%7D%2B%5Csqrt%7Bc%7D%5Cqquad%20%5Cqquad%5B1%5D)
![b=\sqrt{63}+\sqrt{d}\qquad \qquad[2]](https://tex.z-dn.net/?f=b%3D%5Csqrt%7B63%7D%2B%5Csqrt%7Bd%7D%5Cqquad%20%5Cqquad%5B2%5D)
![\displaystyle \frac{c}{d}=\frac{1}{9} \qquad \qquad [3]](https://tex.z-dn.net/?f=%5Cdisplaystyle%20%5Cfrac%7Bc%7D%7Bd%7D%3D%5Cfrac%7B1%7D%7B9%7D%20%5Cqquad%20%5Cqquad%20%5B3%5D)
From [3]:

Replacing into [2]:

We can express 63=9*7:

Taking the square root of 9:

Factoring:

Find the ration a:b:

Simplifying:
