Answer:
24 cm²
Step-by-step explanation:
You can show your sister how to use the formula for the area of a triangle.
The base dimension is substituted for the letter b, the height is substituted for the letter h, and then the arithmetic is carried out.
A = 1/2bh
A = (1/2)(12)(4) = (6)(4) = 24 . . . . square centimeters
