The first time I tried this problem I found it challenging because I wasn’t sure how to factor the 9 out of the first square root. I was also intimidated by the combination of x with the negative sign and the two 9s in the problem, and I thought that factoring wouldn’t be simple in this case.  

Describe the mistake/problem that happened the first time you tried it. 

The mistake that I made was that I didn’t factor out the GCF properly and skipped a step. I ended up factoring the GCF out of both sides of the negative sign and transferring them out of the square root in one step, which led to an incorrect answer. 

What strategies did you use to figure it out?

When figuring this problem out, I initially tried the problem again, thinking I had made a small error. When I got the same answer, I asked Ms. Lam for help during my Flex block and she helped me to recognize my mistake. I took this new information and used it when I encountered similar problems in the workbook. 

Which concepts and/or skills did you need to be able to solve this problem?

The concepts and skills that I needed to solve this problem were factoring out a GCF, simplifying radicals, and adding and subtracting radical expressions. 

Next time I encounter a difficult problem, I might try watching a video on YouTube that goes over the concept so that I might identify the mistake I made by myself. I might also work backwards after looking at the answer key in the workbook.