notebooks=x pens=y 7=2x+y 8=x+5y ==> x=8-5y substitute into the first equation 7=2(8-5y)+y 7=16-10y+y 7=16-9y -9=-9y y=1 now substitute y to find x x=8-5y x=8-5(1) x=8-5 x=3 assuming you want amount of money for each item, a notebook is $3, and a pen is $1.
