Question

已知：a=10,b=3;则表达式：a

Answer 1

x/(x-5)=3+a/(5-x)

x=3(x-5)-a

x=3x-15-a

2x=15+a

x=(15+a)/2

当x=5时原方程x/(x-5)=3+a/(5-x)无解,所以,令（15+a）/2=5,得a=-5