<span>Subtract equation 1a) from equation 2a) to get </span>
<span>n = 1.45 ...................... that's the cost of one notebook </span>
<span>~~~~~~~~ </span> <span>To check, you could go on to figure out p, which turns out to be 0.60 . Put in those values of n and p into the original equations to verify.</span> Hope this helps! ~Nadia~