The answer is 270 cm²
The area (A) of a triangle with base b and height h is:
A = b h / 2
A = 30 cm²
Since the base and height are scaled by a factor of 3, that means that they are increased 3 times:
b1 = 3b
h1 = 3h
A1 = b1 h1 /2
A1 = 3b 3h / 2
A1 = 3 3 b h / 2
A1 = 9 b h / 2
A1 = 9 A
A1 = 9 30 cm²
A1 = 270 cm²
