Answer:
Figures A,D are polygons.
Reason:
Polygon is a closed figure with atleast three strange lines and angles.
First, create an equation with the criteria given.
If we let x be your number,

(

is twice the product of 3 and x, and if it exceeds

by 10, then we add 10 to

to make the two sides of the equation equal.)
Now, solve for

.
Answer:
cos(O) = 39 / 89
Step-by-step explanation:
Given:
ΔOPQ, where
∠Q=90°
PO = 89
OQ = 39
QP = 80
cosine of ∠O?
cos(O) = Adjacent / Hypotenuse
cos(O) = 39 / 89