20 of 2320 of 23 Items

Question
Solve the logarithmic equation ln(3x−11)=ln(4+2x)
.(1 point)
x=

1 answer

To solve the equation \( \ln(3x - 11) = \ln(4 + 2x) \), we can use the property that if \( \ln(a) = \ln(b) \), then \( a = b \). Thus, we set the arguments of the logarithms equal to each other:

\[ 3x - 11 = 4 + 2x \]

Now, we will solve for \( x \). Let's first isolate \( x \) by rearranging the equation:

  1. Subtract \( 2x \) from both sides: \[ 3x - 2x - 11 = 4 \] This simplifies to: \[ x - 11 = 4 \]

  2. Now, add \( 11 \) to both sides: \[ x = 4 + 11 \] Thus, we have: \[ x = 15 \]

Now, we need to check if this solution is valid by substituting \( x = 15 \) back into the original arguments of the logarithm:

  • For \( 3x - 11 \): \[ 3(15) - 11 = 45 - 11 = 34 \]

  • For \( 4 + 2x \): \[ 4 + 2(15) = 4 + 30 = 34 \]

Both arguments are equal and positive, which means our solution is valid.

Therefore, the solution to the logarithmic equation is: \[ \boxed{15} \]