Answer:
11. #1 90 degrees
#2 45 degrees
#3 45 degrees
#4 90 degrees
12. 6x-21 = 45
add 21 to both sides
6x= 66
Divide by 6
66/6=11 so x=11
13. Rectangle and square I think
14. All of them
15. Square and rhombus
16. All of them
