See attache picture for answer
The polygon in option 3 is not octagon at all, it is heptagon (or 7-sided polygon).
A convex octagon has no angles pointing inwards. More precisely, no internal angles can be more than 180°.
When some internal angle is greater than 180°, it is concave.
In option 2 you can see that one angle is pointing inward, then this octagon is concave.
Answer: correct choice is B.
Libby wants to make cookies for her whole class. There are 36 students in her class. The recipe Libby is going to use only makes 12 cookies. How many batches of cookies is Libby going to have to make to feed her whole class?
36/12
I think the answer would be 38in^2
Because the equation is : (a+b) *h / 2
A and b are both the bases of the trapezium
So (11 + 8) these are the bases and the height is 4 so you would do
(11+8)*4 / 2
(19)*4 / 2
76 / 2
= 38