1) factor to see if you can get anything to cancel out before you multiply
2) the rest of my work is shown in the picture attached
3) the answer is n^2
Sum of interior angles in a pentagon=540°
148+112+2x+2x+10+90=540
360+4x=540
4x=540-360
4x=180
x=180/4
x=45°
I don't understand what your point is. Mind posting a picture or something?
Two squares root. Because 3 * 3 = 9 and -3 * -3 = 9.
The area of a circle is equal to:

r = 1/2 the diameter
1/2 of 14 is 7
7 squared is 49
<em><u>The area is 49π</u></em>