It looks like he used the distributive property. He multiplied 7*2. Then. 7*6. Then he multiplied them together. That is not how you multiply numbers
Answer:
720
Step-by-step explanation:
We can use the Pythagorean theorum
a^2+b^2=c^2
c^2 is the length of the longest side squared
so
6^2 + b^2 = 10^2
36+ b^2 = 100
-36 -36
b^2 = 64
b = 8
b is the same thing as your "x", so x = 8
The exterior angles of a polygon all add to 360, if you need to find an exterior angle when given the number of sides and that all angles are equal you simply do: 360/ number of sides.
When you need to find the exterior angle when given an interior angle, you do: 180- interior angle.
Hope this helps :)