Question

The linear function graphed below represents the value of a comic book since Lucy purchased it. What was the value of the comic book when Lucy bought it?

A graph titled Value of Lucy' s Comic Book has Years since Lucy bought comic book on the x-axis, and value (dollars) on the y-axis. Points are at (1, 40), (2, 55), (3, 70), (4, 85).
$10
$15
$25
$40

Answer 1

25

The value increases by \$15 each year (40 → 55 → 70 → 85), so at year 0 it's \$40 − \$15 = \$25 (or use y = 15x + 25).