Please answer this question Thank u !!

Step-by-step explanation:

The system of equations (a) is the correct one for this situation.  We must now solve this system for x and y, which are the unit costs.

Multiplying the 2nd equation by (-3/2) yields -12x - 18y = -168.

Now eliminate x by combining the two equations

12x + 5 y = 116

-12x  -18y  = - 168

         -13y = -52, or y = 4.

If y = 4 then 12x + 5y = 116, or

                    12x  +5(4) = 116, or

                     12x  +  20  =  116, or

                      12x       = 96, or x = 8

Roller pens are $8/dozen and ball point pens are $4 per dozen.

good luck!

cutie~

this is answer of 144 cubic meters