Answer:
18
Step-by-step explanation:
The summation symbol is telling you there are 4 terms of the sum. The values of x in the terms range from 1 to 4.
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The expanded form of the sum is ...
(1 +2) +(2 +2) +(3 +2) +(4 +2)
= 3 +4 +5 +6 = 18
The sum is 18.
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Additional comment
The sum can be rewritten as ...
[tex]\displaystyle \sum_{x=1}^4{(x+2)}=\sum_{x=1}^4{x}+\sum_{x=1}^4{2}=\dfrac{4(4+1)}{2}+4\times2=10+8=\boxed{18}[/tex]
This way, you need to know the sum of integers from 1 to n is (n/2)(n+1). It may be easier just to write the terms out as we have done above.
