Answer:
- Vertices:(-14,4) and (10,4).
- Foci: (–17, 4) and (13, 4)
Step-by-step explanation:
Given the equation of the hyperbola

Since the x part is added, then

Also, this hyperbola's foci and vertices are to the left and right of the center, on a horizontal line paralleling the x-axis.
From the equation, clearly the center is at (h, k) = (–2, 4). Since the vertices are a = 12 units to either side, then they are at (-14,4) and (10,4).
From the equation

The foci, being 15 units to either side of the center, must be at (–17, 4) and (13, 4)
3025 is a perfect square, so just take the square root.
sqrt(3025) = 55
The chord that goes through the center of a circle, the diameter, is the longest chord in a circle. Any other chord will be shorter than this. The farther a chord is away from the circle, the shorter it will be. This means that chord CD is shorter than chord AB.
Answer:
Leo is 11 years old
Step-by-step explanation:
* Lets explain how to solve the problem
- Alea is 5 times 3 less than leo's age
- Alea is 40 years old
- Assume that leo's age is x
* Lets change the words to equation
∵ Leo is x years old
∵ Alea is 5 times 3 less than Leo's age
- That means when we subtract 3 from Leo's age and multiply the
difference by 5 the result is Alea's age
∴ Alea's age = 5(x - 3)
- Multiply the two terms of the bracket by 5
∴ Alea's age = 5x - 15
∵ Alea is 40 years old
- Equate the expression of Alea's age by her age
∴ 5x - 15 = 40 ⇒ the equation to find Leo's age
- Add 15 to both sides
∴ 5x = 55
- Divide both sides by 5
∴ x = 11 ⇒ the solution of the equation
∵ x represents the Leo's age
∵ x = 11
∴ Leo is 11 years old
Remark
You have to complete the square twice. Begin by transferring the 75 to the right hand side. Put separate brackets around the x terms and another set around the y terms.
(x^2 + 10x ) + (y^2 - 16x ) = - 75
(x^2 + 10x + (10/2)^2 ) + (y^2 - 16x + (16/2)^2) = - 75 + (10/2)^2 + (16/2)^2
(x + 5)^2 + (y - 8)^2 = - 75 + 25 + 64
(x + 5)^2 + (y - 8)^2 = 14
The center is at (-5,8) which is C
Note: The graph is below just to confirm my answer. Notice where the center is and that the radius is just under 4.