Compute successive differences of the terms.
If they are all the same, the sequence is arithmetic and the common difference is the difference you have found.
If successive pairs of differences have the same ratio, the sequence is geometric and the common ratio is the ratio you have determined.
Example of arithmetic sequence:
1, 3, 5, 7
Successive differences are 3-1 = 2, 5-3 = 2, 7-5 = 2. All the differences are 2, which is the common difference of the sequence.
Example of geometric sequence:
1, -3, 9, -27
Successive differences are -3-1 = -4, 9-(-3) = 12, -27-9 = -36. These are not the same, so the sequence is not arithmetic. Ratios of successive pairs of differences are 12/-4 = -3, -36/12 = -3. These are the same, so the sequence is geometric with common ratio -3.
A. Alright, we want to multiply one equation by a constant to make it cancel out with the second. Since the first equation has a "blank" y, let's multiply the first equation by <em>2</em>.
3x-y=0 → 2(3x-y=0) = 6x - 2y = 0
5x+2y=22
The answer for this part would be: 6x - 2y = 0 and 5x + 2y = 22
B. So now we combine them:
6x - 2y = 0
+ + +
5x + 2y = 22
= = =
11x + 0 = 22 ← The answer
C. Now that we have the equation 11x = 22, we solve for x
11x = 22 ← Divide both sides by 11
x = 2 ← The answer
D. Now that we have x=2, we plug that back in to 5x+2y=22 and solve for y:
5(2)+2y = 22
10 + 2y = 22
2y = 12
y = 6
<u>Therefore, the solution to this problem is x = 2 and y = 6</u>
Answer:
20
Step-by-step explanation:
10- 10, <u>20</u>, 30, 40 ,50
4- 4, 8, 12, 16, <u>20</u>
Answer:
25b?
Step-by-step explanation:
Answer: The odds of getting tails twice in a row are 1/2 * 1/2 = 1/4. So 25% of the time you'll get heads twice in a row. But, if you've already flipped a coin 99 times, and gotten heads each time, then the odds of your next flip being heads is still just 50:50.
Step-by-step explanation:
