Respuesta :

dummyatmath

Answer:

4+2b=5+5b+20

<=> -3b=21

<=> b=-7

Step-by-step explanation:

<=> 4+2b=5+5b+5×4

<=> 4+2b=5+5b+20

<=> 2b-5b=5-4+20

<=> -3b=21

<=> b=-21/3

<=> b=-7