The base is 315. Perimeter of base is 72.
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°
When you are finding the area, you multiply the length x the width. So for example, we have a rectangle that the length is 6 feet and the width is 4 feet. So, first of all we multiply 6x4= 24. Since its area don't forget it is Square Feet (or any other type of measurement).
Hope it helps!