4x37
Step-by-step explanation:
only a few ways to get to 148
The sum of the 8 terms of the series 1-1-3-5- ... -13 is -48
The given sequence is:
1,-1,-3, . . -13
and there are 8 terms.
The related series of this sequence is:
1-1-3-5- ... -13
Notice that the series is an arithmetic series with:
first term, a(1) = 1
common difference, d = -1 - (1) = -2
last term, a(8) = -13
To find the sum of the series, use the sum formula:
S(n) = n/2 [(a(1) + a(n)]
Substitute n = 8, a(1) = 1, a(n) = a(8) = -13 into the formula:
S(8) = 8/2 [1 + (-13)]
S(9) = 4 . (-12) = -48
Learn more about sum of a series here:
brainly.com/question/14203928
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Answer:
-3
Step-by-step explanation:
Isolate -3y by subtracting x from both sides
-3y = -18 - x
Divide everything by -3
y = 6 + 1/3x
Slope is 1/3, and perpendicular lines have the reverse reciprocal slope, so our slope is -3
Answer:
x=8 or -8
Step-by-step explanation:
64 squared = 8 or -8
8x8=64
-8x-8 = 64
Answer: 41.5 min
Step-by-step explanation:
This problem can be solved with the Radioactive Half Life Formula:
(1)
Where:
is the final amount of the radioactive element
is the initial amount of the radioactive element
is the time elapsed
is the half life of the radioactive element
So, we need to substitute the given values and find from (1):
(2)
(3)
(4)
Applying natural logarithm in both sides:
(5)
(6)
Clearing :
This is the time elapsed
