SOLUTION: I need help, step by step on how to solve ln (x +7) + ln (x + 3) = ln 77

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Question 354826: I need help, step by step on how to solve ln (x +7) + ln (x + 3) = ln 77
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
+ln%28x+%2B7%29+%2B+ln%28x+%2B+3%29+=+ln%2877%29
+ln%28%28x+%2B7%29%28x+%2B+3%29%29+=+ln%2877%29
%28x+%2B7%29%28x+%2B+3%29+=+77
x%5E2%2B3x%2B7x%2B21=77
x%5E2%2B10x%2B21=77
x%5E2%2B10x=56
x%5E2%2B10x%2B25=56%2B25
%28x%2B5%29%5E2=81
x%2B5=0+%2B-+9
x=5+%2B-+9
x1=14 and x2=-4
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However since ln%28-4%2B3%29=ln%28-1%29 is undefined, only highlight%28x=14%29 is a valid solution.