Respuesta :

garcialnatalia
These are the equations given:
31=B+J
B=2J+4

So you substitute B=2J+4 into 31=B+J

31=2J+4+J

Solve

31-4=3J+4-4
27=3J
27/3=3J/3
9=J

Jake has 9 cd's.

Answer:

j = 9 (# of CDs Jake has)

Step-by-step explanation:

Equations::

b + j = 31 CDs

b = 2j+4

-----

Substitute for "b" and solve for "j"::


2j+4 + j = 31

3j = 27

j = 9 (# of CDs Jake has)