Respuesta :

sqrt(20)+sqrt(45)-sqrt(5)=sqrt(4*5)+sqrt(9*5)-sqrt(5)
sqrt(20)+sqrt(45)-sqrt(5)=sqrt(4)*sqrt(5)+sqrt(9)*sqrt(5)-sqrt(5)
sqrt(20)+sqrt(45)-sqrt(5)=2*sqrt(5)+3*sqrt(5)-sqrt(5)
sqrt(20)+sqrt(45)-sqrt(5)=4*sqrt(5)

Answer: Third option 4 sqrt(5)