Answer:

Step-by-step explanation:
The standard equation of a hyperbola is given by:

where (h, k) is the center, the vertex is at (h ± a, k), the foci is at (h ± c, k) and c² = a² + b²
Since the hyperbola is centered at the origin, hence (h, k) = (0, 0)
The vertices is (h ± a, k) = (±√61, 0). Therefore a = √61
The foci is (h ± c, k) = (±√98, 0). Therefore c = √98
Hence:
c² = a² + b²
(√98)² = (√61)² + b²
98 = 61 + b²
b² = 37
b = √37
Hence the equation of the hyperbola is:

<u>Given</u>:
Four lines are marked proportion, the length of TW can be determined by

<u>Value of a:</u>
Let us set the proportion for the given lines.
Thus, we have;



Thus, the value of a is 5.6
<u>Value of b:</u>
Let us set the proportion for the given lines.
Thus, we have;



Thus, the value of b is 5.
<u>Length of TW:</u>
The length of TW is given by


Thus, the length of TW is 13.6
Blaire has 20 tomato plants altogether.
Step-by-step explanation:
Given,
Tomatoes plants ready to pick = 18
This represents 90% of total tomato plants.
Let,
x be the original number of tomato plants.
90% of x = 18


Dividing both sides by 0.9


Blaire has 20 tomato plants altogether.
Keywords: percentage, division
Learn more about division at:
#LearnwithBrainly
Answer:
Both A and B are true identities
Step-by-step explanation:
A. N ( n − 2 ) ( n + 2 ) = n 3 − 4 n
We need to show that (left-hand-side)L.H.S = R.H.S (right-hand-side)
So,
n ( n − 2 ) ( n + 2 ) = n(n² - 2²) (difference of two squares)
= n³ - 2²n (expanding the brackets)
= n³ - 4n (simplifying)
So, L.H.S = R.H.S
B. ( x + 1 )² − 2x + y² = x² + y² + 1
We need to show that (left-hand-side)L.H.S = R.H.S (right-hand-side)
So,
( x + 1 )² − 2x + y² = x² + 2x + 1 - 2x + y² (expanding the brackets)
= x² + 2x - 2x + 1 + y² (collecting like terms)
= x² + 1 + y²
= x² + y² + 1 (re-arranging)
So, L.H.S = R.H.S
So, both A and B are true identities since we have been able to show that L.H.S = R.H.S in both situations.