19. B.
20. J.
Hope this helps :P
The answer is: A. 20.3
The explanation is shown below:
1. By definition, the sum of the length of the strings (The length of the blue segment and the length of the red segment) is equal to the length of the major axis (The black segment).
2. Based on this, you can write the following expression, where
is the length of the blue segment:

3. Now, you must solve for
, as following:


4. Therefore, the answer is the option A.
The steps taken to find the √5 using the ancient method is;
5/G1 = 2.5
5/G2 = 2.222
5/G3 = 2.236
We want to find √5 with the ancient Babylonian method for calculating non-perfect squares;
We are told that G1 = 2
Thus;
5/G1 = 2.5
We are told to average 2.25 and G2 to get 2.236
This means that;
(2.25 + G2)/2 = 2.236
2.25 + G2 = 2 × 2.236
G2 = 4.472 - 2.25
G2 = 2.222
Second step is;
5/G2 = 2.222
Finally;
5/G3 = 2.236
Read more about finding non-perfect squares at; brainly.com/question/9165533
Step-by-step explanation:
7x + 8 + 15 - 7x
Solving like terms
23
Option C is the correct answer