SOLUTION: how do you solve the problem ln (y+2) = ln (y-7) + ln 4?

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Question 434450: how do you solve the problem ln (y+2) = ln (y-7) + ln 4?
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!
ln+%28y%2B2%29+=+ln+%28y-7%29+%2B+ln+4.............use the rule ln+%28u%29+%2B+ln+%28v%29=ln%28uv%29
ln+%28y%2B2%29++=+ln+%284%28y-7%29%29
y%2B2++=+4%28y-7%29
y%2B2++=+4y-28
28%2B2++=+4y-y
30+=+3y
y=10
check:
ln+%2810%2B2%29+=+ln+%2810-7%29+%2B+ln+4..........
ln+%2812%29+=+ln+%283%29+%2B+ln+4.........
2.485=+1.099+%2B+1.386.........
2.485=+2.485.........