K + j = 54

j = k - 30

How many shells does Joshua have?

j=?

12

Step-by-step explanation:

To solve, substitute the value for k into one of the equations.

We know that k + j = 54.

To get k alone, subtract j. k = - j + 54.

Plug the value of k into the second equation. j = - j + 54 - 30.

Simplify.

j = - j + 24

2j = 24

j = 12