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

2016-06-28T19:41:24+08:00
2.)
m=a+b/2
8=3+3x+5/2
16=3+3x+5 (nag,cross multiply po tayo. kaya ito ang result)
16=8+3x (combining like terms)
16-8=3x
8=3x
8/3=3x/3
2.67=x

That's all. God bless.
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