Answer:
7.5 cm²
Step-by-step explanation:
Dimensions of the large ∆:


Dimensions of the small ∆:


Difference between the area of the large and the small ∆ = 13.5 - 6 = 7.5 cm²
I'm not sure
Step-by-step explanation:
Answer:
80 degrees
Step-by-step explanation:
Do 90 plus 10.
The do 180 minus 100
because a triangle adds up to 180