Question

выполните сложение дробей$\frac{5b}{4-b} +\frac{20}{b-4} ' b\neq 4$

Answer 1

5b/(4-b)+20/(b-4)=

5b/(4-b)-20/(4-b)=

(5b-20)/(4-b)=-5(4-b)/(4-b)=-5