Answer:
x = 135 degrees
Step-by-step explanation:
For any simple n-gon, the sum of the interior angles is 180(n − 2) degrees. (n is the number of vertices)
180(6-2)=180(4)=720
the shape already has 2 90-degree angles, subtract both of those from total interior angle sum
720-90-90=540
the 4 angles left must make up 540 degrees
540/4=135
x=135 degrees
What's a regular heptagon? "Hept-" means seven, so a "heptagon" is a seven-sided shape. A "regular" figure's sides are all the same length. So, each of the 7 sides are the same length.
Remember, perimeter is the sum of the lengths of all the sides in a polygon. We know one side measures three inches, so each of the others must also measure 3 inches. 3+3+3+3+3+3+3=3*7=21 inches.
Answer: 21 inches