Answer:
3500 cm²
Explanation:
The given triangle has an area of ...
A = (1/2)bh = (1/2)(10 cm)(7 cm) = 35 cm²
The area of the enlarged triangle will be 10² = 100 times that, or 3500 cm².
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You can see this if you use the enlarged dimensions in the area formula:
A = (1/2)bh = (1/2)(10·10 cm)(10·7 cm) = 100·35 cm² = 3500 cm