Do (10 x 10) then (10 x 20), and then add your two answers together.
Its simple :)
Answer:
3
Step-by-step explanation:
Formula:

= 3
Answer: 8.9 units (choice C)
Explanation:
We plug
into the distance formula to get the following

Area of a triangle = (height * base ) / 2
height = (Area * 2) / base
height = (49.5 * 2) / 9
height = 99 / 9
height = 10 cm²