We have been given work of Riley. By looking at his work carefully, we have to identify the error. So let's start from beginning.
[tex] \frac{x}{x^2-5x+6}+ \frac{3}{x+3} [/tex]
First line is just the question so there will be no error.
After that we try to factor denominators
STEP1: [tex] \frac{x}{(x-2)(x-3)}+ \frac{3}{x+3} [/tex]
Factors are correct so no error in step1.
In step2, we have to find the common denominator which will be (x-2)(x-3)(x+3)
so that means she needs to multiply and divide 2nd term by (x-2)(x-3) while she multiplied by only (x-2). Which means she used wrong common denominator.
Hence final answer will be "B. She used the wrong common denominator."
