30, 6+9= 15+4= 19+1= 20+10= 30
Answer:
Slide to the left then rotate 90° to the right then slide down then rotate 180° to the left/ right.
The sum of the inner angles of a polygon with n sides is 
Since your polygon has 6 sides, the sum of its inner angles has to be

On the other hand, the sum of its inner angles is

And it has to be 720, so we have

2L + 2(L-6) = 68
2L + 2L -12 = 68
4L = 80
L = 20
The length is 20 in. and the width is 14 in.