When you see questions with dirrerent scales, find the scale factor first.
Scale factor
= A ÷ A’ = 12 ÷ 4 = 3
Larger flag perimeter = 3 × 16 = 48 units
D=√(x2-x1)² + (y2-y1)²
D=√(-6 3/4-8 1/2)² + (7 1/2-12)²
D=√(-15 1/4)² + (-4 1/2)²
D=√3721/16 + 81/4
D=√4069/16
D=64/4
D=16