Voicethread: Solving Log Equations II

In the second voicethread on solving logarithmic equations, we were introduced to something new :O ! We learned what to do when the solution to a log. equation becomes a quadratic equation! We must simply find the 2 solutions to our quadratic equation, then verify them by plugging them individually into our original log. equation. They are only solutions if they give a log with a positive argument. For example:

log(x+3)+logx=2

log((x+3)x)=2

10^2 = x^2 +3x

 x^2 + 3x-100=0

Quadratic Equation!

solutions:  8.6     -11.6

log(8.6+3)         log(8.6)   ✔
log(-11.6+3)     log(-11.6)   X