For this case we have the following data:
So that the figure can be a rectangle, its diagonals must be equal, that is, 
In this way we have:
Clearing x we have:
Thus, x must be equal to 10 so that the figure is a rectangle.
Answer:
Option A
Answer:
Step-by-step explanation:
<u>Given equation:</u>
- x² + y² + 8x - 4y - 7 = 0
<u>Convert this to standard form by completing the square:</u>
- (x - h)² + (y - k)² = r², where (h, k) - center, r - radius
- x² + 2*4x + 4² + y² - 2*2y + 2² - 16 - 4 - 7 = 0
- (x + 4)² + (y - 2)² - 27 = 0
- (x + 4)² + (y - 2)² = 27
- (x + 4)² + (y - 2)² = (√27)²
The center is (- 4, 2) and the radius is √27
Rules for SN = must be a number from 1 and less than 10 times a power of 10
So our number becomes
2.22 x 10⁸ - It takes a move of 8 places to the right to make the number 222,000,000
