SOLUTION: given the sequence : 2x-3,7x,11x; find x if the sequence is 1.) arithmetic 2.) geometric(x 0)

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Question 476378: given the sequence : 2x-3,7x,11x; find x if the sequence is
1.) arithmetic
2.) geometric(x 0)
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
1.) arithmetic
a%5B1%5D=2x-3, a%5B2%5D=7x,a%5B3%5D=11x
a%5B2%5D-a%5B1%5D=a%5B3%5D-a%5B2%5D
7x-%282x-3%29=11x-7x
7x-2x%2B3=4x
5x-4x=-3
x=-3
.
.
.
2.) geometric
a%5B1%5D=2x-3, a%5B2%5D=7x,a%5B3%5D=11x
a%5B2%5D%2Fa%5B1%5D=a%5B3%5D%2Fa%5B2%5D
7x%2F%282x-3%29=11x%2F7x
7x%2F%282x-3%29=11%2F7
7x%2A7=%282x-3%29%2A11
49x=22x-33
49x-22x=-33
27x=-33
x=-33%2F27
x=-11%2F9