1. Solving Logarithmic Equations

2. We need to solve log equations to find the y intercept. We’ll use the log properties to help us do that. Type 1:

3. Take the Log or In of both sides. Use the power property to bring the exponents down.

4. Remember log5 and log3 are just decimals so we can either distribute them through and then collect like terms, etc. OR…. Or divide both sides by one of them

5. Distribute, collect like-terms, etc. x – 3 = 1.36x -.6826 -1.36x + 3 -1.36x +3 x – 3 = 1.36x -.6826 x =-6.437

6. Your turn…..

10. Type 2: Notice: 1. log with same base on both sides. 2. logs are ALONE. Nothing is multiplied or added on. For example:

11. Type 2: When we have THIS situation and this situation ONLY the logs can be cancelled.

12. Type 2: And then it’s easy to solve!

13. Type 3: Notice: ONLY one “log” So MUST rewrite into exponential form

14. Type 3: And then it’s easy to solve!

15. p. 519 4- 36 evens