1.)what are the first and last term of an arithmetic sequence. when its arithmetic means are 35, 15 and -5
with solution pls :)

2.)Find the value of x if the arithmetic mean of 3 and 3x+5 is 8.
with solution pls ;)

3.)Find the value of a when the arithmetic mean of a+7 and 3a+9.
with solution pls. :) :)

1

Answers

2016-06-26T21:33:11+08:00
1. 55,36,15,-5,-25
2. idk
3. a=1
1+7+1+3=12
3(1)+9 =12
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