Problem: When x is added to both the numerator and the denominator of the fraction baβ,aξ =b,bξ =0, the value of the fraction is changed to dcβ. Then x equals:
Answer Choices:
A. cβd1β
B. cβdadβbcβ
C. c+dadβbcβ
D. cβdbcβadβ
E. c+dbcβadβ
Solution:
b+xa+xβ=dcββ΄ad+xd=bc+xcβ΄adβbc=x(cβd)β΄x=cβdadβbcβ
Comment. If dcβ=abβ,x=β(a+b).