Answer:
L = 48
Explanation:
Given that L varies directly with Z² , then the equation relating them is
L = kZ² ← k is the constant of variation
To find k use the condition L = 12 when Z = 2 , then
12 = k × 2² = 4k ( divide both sides by 4 )
3 = k
L = 3Z² ← equation of variation
When Z = 4 , then
L = 3 × 4² = 3 × 16 = 48