13.8 is bigger being a positive number.
Answer:
324 cm²
Step-by-step explanation:
→ Work out perimeter of square
72 + 72 + 72 + 72 = 288
→ Work out the width of the rectangle
288 - (90 × 2) = 108
108 ÷ 2 = 54
→ Work out area of square
72 × 72 = 5184 cm²
→ Work out area of rectangle
90 × 54 = 4860 cm²
→ Minus the areas from each other
5184 cm² - 4860 cm² = 324 cm²
The answer is I believe: 21