Answer: B, C, E
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The difference between consecutive terms (numbers that come after each other) in arithmetic sequences is the same. That means you add the same number every time to get the next number. To figure out which choices are arithmetic sequences, just see if the differences are the same.
Choice A) 1, -2, 3, -4, 5, ...
-2 - 1 = -3
3 - (-2) = 5
The difference is not constant, so it is not an arithmetic sequence.
Choice B) 12,345, 12,346, 12,347, 12,348, 12,349, ...
12,346 - 12,345 = 1
12,347 - 12,346 = 1
The difference is constant, so it is an arithmetic sequence.
Choice C) <span>154, 171, 188, 205, 222, ...
171 - 154 = 17
188 - 171 = 17
The difference is constant, so it is an arithmetic sequence.
Choice D) </span><span>1, 8, 16, 24, 32, ...
8 - 1 = 7
16 - 8 = 8
</span>The difference is not constant, so it is not an arithmetic sequence.
Choice E) <span>-3, -10, -17, -24, -31, ...
-10 - (-3) = -7
-17 - (-10) = -7
</span>The difference is constant, so it is an arithmetic sequence.
Since the total measure of all the angles of a triangle is always 180, solve for x with the equation: 3x+1+2x-3+9x=180. x=13. Now plug in x and look for the smallest one, which will be B. 23 degrees.
Answer:
C. 
Step-by-step explanation:
You can solve this in two ways, firstly by eliminating all the wrong answers, and secondly by just knowing that the horizontal line in 
means that we are talking about a line.
This is how we solve this question by using the eliminating process.
(A. ∠C) is not the right answer because the ∠ sign lets us know that this answer represents an angle, not a line
(B. <em>B) </em>is not the right answer because it represent a point, not a line (in math we use a singular capital letter to represent points)
(D. ΔABC) is not the right answer because the Δ sign lets us know that the answer represents a triangle, not a line.
Therefore, the only option left is C.
Question 10: P=28cm
if l=8 and w=6
Then (8+6)=14
2(14) so 14x2 = 28
So therefore P=28cm
