1. Lesson 6.6 Solving Exponential and Logarithmic Equations Day 2
Learning Goal: (F.LE.A.4, A-REI.A.1)
I can solve logarithmic equations by using the properties of logarithms.
I can explain each step in solving a logarithmic equation.
Essential Question: How can you solve logarithmic equations?
Homework #11 Discussion

2. Solving Logarithmic Equations
logbx = logby if and only if x = y
( b, x and y are positive, b≠1 )
Examples: Solve. Explain each step. Check for extraneous solutions.
(a) ln(4x − 7) = ln(x + 5)
(b) log2(5x − 17) = 3
Your Turn
Solve. Explain each step. Check for extraneous solutions.
(a) log(4x − 7) = log(x + 5)
(b) ln(5x − 17) = 3

3. Examples: Solve. Explain each step.
1. log 2x + log(x − 5) = 2.
2. 2 log x - log 4 = 2
Your Turn
Solve. Explain each step.
1. log6 6x + log6(x − 1) = 2.

4. Group Consensus
Solve the equation. Check for extraneous solutions.
1. ln(7x − 4) = ln(2x + 11) log2(x − 6) = 5
3. log 5x + log(x − 1) = log4(x + 12) + log4 x = 3

5. Practice to Strengthen Understanding
Exit Question
Why is it important to check your solution when solving logarithmic equations?
Practice to Strengthen Understanding
Hmwk #12 BI p338-9 #21-32all, even