If the 5 scores have a mean of 8, then their total sum would be 8*5 = 40
Now if one score if added (let's call this score x), there are 6 scores and the mean changes to 9, thus:
(40 + x)/6 = 9
40 + x = 54
x = 14
Rule: The diagonals of any parallelogram bisect each other. In other words, they cut each other in half.
This means DF is cut into two equal pieces: DH and HF.
Similarly, GE is cut into two equal pieces: GH and HE.
DH = HF
x+5 = 2y
x = 2y-5
GH = HE
4x-3 = 4y+1
4(x)-3 = 4y+1
4(2y-5)-3 = 4y+1 ... x has been replaced with 2y-5
8y-20-3 = 4y+1
8y-23 = 4y+1
8y-4y = 1+23
4y = 24
y = 6
If y = 6, then x is
x = 2y-5
x = 2(6)-5
x = 12-5
x = 7
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Answers:
x = 7 and y = 6
Looks complicated, sorry wish I could help
Pretty sure its 132
Hope this helps!
