If an island's only residents are penguins and bears, and if there are 14 heads and 30 feet on the island, how many penguins and how many bears are on the island?

Penguins (P) : 1 H + 2 Ft

Bears (B) : 1 H + 4Ft

Heads Equation: 1P + 1B = 14 → - 2 (1P + 1B = 14) → - 2P - 2B = - 28

Feet Equation: 2P + 4B = 30 → 1 (2P + 4B = 30) → 2P + 4B = 30

2B = 2

B = 1

Heads Equation: 1P + 1B = 14 → 1P + 1 (1) = 14 → P = 13

Answer: 13 Penguins and 1 Bear