SOLUTION: Please help me solve this: log(x^2 + 11x + 8) - log(x + 1) = 1 thank you!

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Question 1157320: Please help me solve this:
log(x^2 + 11x + 8) - log(x + 1) = 1
thank you!
Found 2 solutions by MathLover1, MathTherapy:
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

log%28x%5E2+%2B+11x+%2B+8%29+-+log%28x+%2B+1%29+=+1

log%28%28x%5E2+%2B+11x+%2B+8%29%2F%28x+%2B+1%29%29+=+1.......write 1 as log%2810%29

log%28%28x%5E2+%2B+11x+%2B+8%29%2F%28x+%2B+1%29%29+=+log%2810%29....if lo same, then

%28x%5E2+%2B+11x+%2B+8%29%2F%28x+%2B+1%29+=+10

x%5E2+%2B+11x+%2B+8+=+10%28x+%2B+1%29

x%5E2+%2B+11x+%2B+8+=+10x+%2B+10

x%5E2+%2B+11x+%2B+8+-10x+-+10=0

x%5E2+%2B+x++-+2=0

x%5E2+%2B+x++-+2=0......write x as -x%2B2x

x%5E2+-x%2B2x++-+2=0

%28x%5E2+-x%29%2B%282x++-+2%29=0

x%28x+-1%29%2B2%28x++-+1%29=0

%28x%2B2%29%28x++-+1%29=0

solutions:
x=-2...... (assuming a complex-valued logarithm)
x=1


Answer by MathTherapy(10552) About Me  (Show Source):
You can put this solution on YOUR website!

Please help me solve this:
log(x^2 + 11x + 8) - log(x + 1) = 1
thank you!




matrix%281%2C3%2C+%28x%5E2+%2B+11x+%2B+8%29%2F%28x+%2B+1%29%2C+%22=%22%2C+10%5E1%29 ----- Converting to EXPONENTIAL form

matrix%281%2C3%2C+x%5E2+%2B+11x+%2B+8%2C+%22=%22%2C+10%28x+%2B+1%29%29 ------- Cross-multiplying

matrix%281%2C3%2C+x%5E2+%2B+11x+-+10x+%2B+8+-+10%2C+%22=%22%2C+0%29

matrix%281%2C3%2C+x%5E2+%2B+x+-+2%2C+%22=%22%2C+0%29 

(x - 1)(x + 2) = 0

highlight_green%28matrix%281%2C3%2C+x%2C+%22=%22%2C+1%29%29            OR             x = - 2 (ignore)

Anyone who tells you otherwise is WRONG and they serve no purpose than to confuse you!