Question 89414
12P+8N=15.00
4P+3N=5.50 NOW MULTIPLY THE SECOND EQUATION BY -3 & ADD:
-12P-9N=-16.50
12P+8N=15.00
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-N=-1.50
N=1.50 PRICE OF THE NOTEBOOK.
12P+8*1.50=15.00
12P+12.00=1500
12P=15.00-12.00
12P=3.00
P=3.00/12
P=.25 COST OF THE PEN.
PROOF
4*.25+3*1.50=5.50
1.00+4.50=5.50
5.50=5.50