9.


A. She used y-values where she should have used x-values.

B. She did not keep the order of the points the same in the numerator and the denominator.

C. She mixed up the x- and y-values.

D. She should have added the values, not subtracted them.

9 A She used yvalues where she should have used xvalues B She did not keep the order of the points the same in the numerator and the denominator C She mixed up class=