SOLUTION: Pattern of squares Stage 1 2 squares Stage 2 6 squares Stage 3 12 squares Stage 4 20 squares Which expression can be used to determine the number of squares at stage

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Question 266440: Pattern of squares
Stage 1 2 squares
Stage 2 6 squares
Stage 3 12 squares
Stage 4 20 squares
Which expression can be used to determine the number of squares at stage n?
A. 5n-3
B. 4n-2
C. 2 n2
D. n2 + n
Answer by drk(1908) About Me  (Show Source):
You can put this solution on YOUR website!
THe answer is (D)
1 x 2 = 2
2 x 3 = 6
3 x 4 = 12
4 x 5 = 20
...
n(n+1) = n^2 + n