A regular decagon has 10 equal sides. An apothem is a perpendicular bisector to the side. This means 2 equal right triangle are formed on each side (20 equal right triangles) or 10 equal isosceles triangles.
Using the 10 equal isosceles triangles and A = .5(base)(height)
Base is a side and height is apothem
Area of regular decagon = 10 × .5 × 8 × 12.3 = 492.0 yd²
Answer: 492.0 yd²
$48.32* (15/100)
= $7.25.
The final answer is $7.25~
The two angles form a right triangle which is 90 degrees.
Add the two to equal 90:
3x-8 + 4x = 90
simplify:
7x-8 = 90
Add 8 to both sides:
7x = 98
Divide both sides by 7:
x = 14
I sure its B i might be wrong tho