172.9
You find it by multiplying each side of the triangle by the height (9) and adding the results together.
A(lateral) = 8 * 9.1 + 3 * 9.1 + 8 * 9.1
= 72.8 + 27.3 + 72.8
= 172.9
Parallelogram area = base * height
240 = base * 20
base = 240 / 20
base = 12 cm
Go to calculator pro it tells you everything by just taking a picture.
The answer would be B. As you can see Angle A and angle B are connected by that line and together they would equal 90 degrees like on the other side of line AB.
