Problem: The equation can be transformed by eliminating fractions to the equation . The roots of the latter equation are and . Then the roots of the first equation are:
Answer Choices:
A. and
B. only
C. only
D. neither nor
E. and some other root
Solution:
Since is not a solution of the original equation, the solution set of the first equation is the number 4 only;
or
the graph of is the straight line with the point deleted. Since the graph crosses the -axis at ( 4,0 ), its only root is .