SOLUTION: please help to solve : {{{log_[3](x+7) + log_[3](2)= log_[3](20)}}}

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Question 68359This question is from textbook An Incremental Development
: please help to solve :
log_%5B3%5D%28x%2B7%29+%2B+log_%5B3%5D%282%29=+log_%5B3%5D%2820%29This question is from textbook An Incremental Development

Answer by jim_thompson5910(21667) About Me  (Show Source):
You can put this solution on YOUR website!
log_%5Bb%5D%28x%29+%2B+log_%5Bb%5D%28y%29=+log_%5Bb%5D%28x%2Ay%29Use this identity to change left side
log_%5B3%5D%28x%2B7%29+%2B+log_%5B3%5D%282%29=+log_%5B3%5D%2820%29Combine left side
log_%5B3%5D%282%2A%28x%2B7%29%29=+log_%5B3%5D%2820%29Get rid of the log's by raising everything to base of 3 (ie undoing the log)
cross%283%29%5E%28%28cross%28log_%5B3%5D%29%282x%2B14%29%29%29=+cross%283%29%5E%28%28cross%28log_%5B3%5D%29%2820%29%29%29
2x%2B14=20Solve for x
x=3