9514 1404 393
Answer:
(a) x^2/16 +y^2/9 = 1
Step-by-step explanation:
The form for the equation of an ellipse centered at the origin is ...
(x/(semi-x-axis))^2 +(y/(semi-y-axis))^2 = 1
The vertex values tell you the semi-x-axis is 4 units, and the semi-y-axis is 3 units. Then you have ...
(x/4)^2 +(y/3)^2 = 1
x^2/16 +y^2/9 = 1
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In case you don't remember that form, you can try any of the points in the equations. The equation that works will quickly become apparent.
The pattern is formed a geometric sequence
The nth term of the sequence is 
Step-by-step explanation:
The formula of the nth term of a geometric sequence is:
, where
- a is the first term
- r is the common ratio between the consecutive terms
∵ The pattern is 3 , 9 , 27 , 81 , 243
∵ 9 ÷ 3 = 3
∵ 27 ÷ 9 = 3
∵ 81 ÷ 27 = 3
∵ 243 ÷ 81 = 3
- There is a common ratio 3 between each two consecutive terms
∴ The pattern is formed a geometric sequence
∵ The first term is 3
∴ a = 3
∵ The common ratio is 3
∴ r = 3
- To find the nth term substitute a and r in the formula above
∵
∴
- Remember we add the powers of the same base with multiplication
∵ 3 ×
= 
∴ 3 ×
= 
∴ 
∴ The nth term of the sequence is
Learn more:
You can learn more about the sequences in brainly.com/question/1522572
#LearnwithBrainly
Answer:
A
Step-by-step explanation:
The sequence of positive odd numbers is
1, 3, 5, 7, ......
This is an arithmetic sequence with common difference d
d = 3 - 1 = 5 - 3 = 7 - 5 = 2
The sum to n terms of an arithmetic sequence is
=
[2a + (n - 1)d ]
where a is the first term
here a = 1, d = 2, n = 12, hence
=
[1 + (11 × 2) ]
= 6 [ 2 + (11 × 2) ]
= 6 × 24 = 144 → A
Answer:
3/4=63/84
66.66%=56/84
5/7=60/84
⇒66.66%; 5/7; 3/4
Step-by-step explanation: