SOLUTION: Find all real or imaginary solution to the question. 6x=-(19x+25)/x+1

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Question 122301: Find all real or imaginary solution to the question.
6x=-(19x+25)/x+1

Found 2 solutions by checkley71, solver91311:
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
6X=-(19X+25)/(X+1) CROSS MULTIPLY.
6X(X+1)=-19X-25
6X^2+6+19X+25=0
6X^2+19X+31=0
using the quadratic equation:x+=+%28-b+%2B-+sqrt%28+b%5E2-4%2Aa%2Ac+%29%29%2F%282%2Aa%29+
x=(-19+-sqrt[19^2-4*6*31])/2*6
x=(-19+-sqrt[361-744])/12
x=(-19+-sqrt-383)/12
x=(-19+-19.57i)/12
x=(-19+19.57i)/12
x=-19/12+-19.57i/12
x=-1.5833+-1.63i answer.

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!



I'm going to assume you meant
6x=-%2819x%2B25%29%2F%28x%2B1%29
rather than
6x=-%2819x%2B25%29%2Fx%2B1

First make a note to exclude x=-1 if it happens to come up as a potential root of the equation because -1 is not in the domain of the right hand side of the equation because -1 would make the denominator equal zero.

Second, move everything to the left of the equal sign, thus:
6x%2B%2819x%2B25%29%2F%28x%2B1%29=0

x%2B1 is your common denominator, so:

%286x%28x%2B1%29%2B%2819x%2B25%29%29%2F%28x%2B1%29=0

Simplify the numerator
%286x%5E2%2B6x%2B19x%2B25%29%2F%28x%2B1%29=0
%286x%5E2%2B25x%2B25%29%2F%28x%2B1%29=0

Remember that a%2Fb=0 if and only if a=0 and b%3C%3E0, meaning that we need to solve for:

6x%5E2%2B25x%2B25=0

Oddly enough, this mess actually factors.

%283x%2B5%29%2A%282x%2B5%29=0, hence

3x%2B5=0
x=-5%2F3
or
2x%2B5=0
x=-5%2F2

Since neither of these roots = -1, both are valid potential roots of the
equation. However, since we introduced an x%5E2 term by applying the
common denominator, we need to check both roots against the possiblity that
one of them is extraneous.

6%28-5%2F3%29=-%2819%28-5%2F3%29%2B25%29%2F%28-5%2F3%2B1%29
-10=-%28-%2895%2F3%29%2B75%2F3%29%2F%28-2%2F3%29
-10=-%28-20%2F3%29%2F%28-2%2F3%29
-10=-%28-20%29%2F%28-2%29
-10=-20%2F2 First root checks.

6%28-5%2F2%29=-%2819%28-5%2F2%29%2B25%29%2F%28-5%2F2%2B1%29
-15=-%28-%2895%2F2%29%2B50%2F2%29%2F%28-3%2F2%29
-15=-%28-45%2F2%29%2F%28-3%2F2%29
-15=-%28-45%29%2F%28-3%29
-15=-45%2F3 Second root checks.

Done