Answer:
4 times bigger
Step-by-step explanation:
1. The area of an object dilated by a scale factor (SF) will be equal to (SF)^2.
2. For example, let's say the base and height of Triangle A is 4 and 8. The area would be 16 units squared. The base and height of Triangle B would be 8 and 16. The area would be 64 units squared.
3. As you can see from the aforementioned example, the SF (2) was squared and then multiplied by 16 to get 64.
Therefore, Triangle B's area is 4 times bigger than Triangle A's area.