Answer:
answer for given question is 108045
The area of the pentagon is 140
Answer : -4a+10
Substitute (a-3) for x
-4(a-3)-2
-4a+12-2
-4a+10 but can also be written as -2(2a-5)
The sum of the angles in a pentagon is 540°.
This means that each angle is 108°.
Inside you pentagon, a triangle is drawn. This triangle is isosceles, because the corners are on the points of the regular pentagon. You know that angle C is 108°.
Angles in a triangle add up to 180°.
B and D will be the same size as this is isosceles.
180°-108° = 72°
This is B and D. You only need one of these, so you divide by 2.
The answer is 36°.
Hope this helps :)