For an inscribed quadrilateral, opposite angles add up to 180 degrees. In this case, if we are looking for the measure of angle D, we can use the fact that angles I & D add up to 180 degrees. Since angle I = 117:
117 + D = 180
D = 63 degrees
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:
1/3
Step-by-step explanation: