Question 958634
F=fiction; N=non-fiction
F+N=12
F=12-N
$12F+$25N=$248 Substitute for F.
$12(12-N)+$25N=$248
$144-$12N+$25N=$248 Subtract $144 from each side.
$13N=$104 Divide each side by 13.
N=8 ANSWER 1: She bought 8 non-fiction books.
F=12-n=12-8=4 ANSWER 2: She bought 4 fiction books.
CHECK:
$12F+$25N=$248
$12(4)+$25(8)=$248
$48+$200=$248
$248=$248