Let S be the sum,
S = 2 + 4 + 6 + ... + 2 (n - 2) + 2 (n - 1) + 2n
Reverse the order of terms:
S = 2n + 2 (n - 1) + 2 (n - 2) + ... + 6 + 4 + 2
Add up terms in the same positions, so that twice the sum is
2S = (2n + 2) + (2n + 2) + (2n + 2) + ... + (2n + 2)
or
2S = n (2n + 2)
Divide both sides by 2 to solve for S :
S = n (n + 1)
Answer: second option.
Step-by-step explanation:
Given the transformation
→
You must substitute the x-coordinate of the point A (which is
) and the y-coordinate of the point A (which is
) into
to find the x-coordinate and the y-coordinate of the image of the point A.
Therefore, you get that the image of A(2,-1) is the following:
You can observe that this matches with the second option.
Answer:
Correct answer is A 357,5
Step-by-step explanation:
At the start the temperature is -7 overnight it gets 12 degrees warmer so -7+12 =5 degrees than during the day it gets 12 degrees warmer so 5+12= 17 degrees