Answer:
49x² + 126x + 81
Explanation:
A = a²
Since a = 7x + 9
=> A = (7x+9)²
= 49x² + 126x + 81
Note: (a+b)² = a² + 2ab + b²
49x²+126x+81
Area of any square is length²
If the length given is 7x+9, we can square this to find out what represents the area:
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