The answer is 400 because u multiply 8 x 10= 80 x 5=400
Answer:
A. x=0
Step-by-step explanation:
x+20+10x=20+9x
cancel equal terms
x+10x+9x
add x to 10x
11x=9x
move variable to left
11x-9x=0
subtract 11x to 9x
2x=0
divide Both sides by 2
x=0
Answer and workings in the attachment below.
Answer:
Actually it's not polygon. it's a nonagon. With r=8.65mm″, the law of cosines gives us side a:
a=√{b²+c²−2bc×cos40°}
a=√{149.645−149.645cos40°}
Area Nonagon = (9/4)a²cos40°
=9/4[149.645−149.645cos40°]cot20°
=336.70125[1−cos(40°)]cot(20°)
Applying an identity for the cos(40°) does not get us very far…
= 336.70125[1−(cos2(20°)−1)]cot(20°)
= 336.70125[2−cos2(20°)]cot(20°)
= 336.70125[2−(1−sin2(20°))]cot(20°)
= 336.70125[1+sin2(20°)]cos(20°)sin(20°)
= 336.70125[cot(20°)+sin(20°)cos(20°)]mm²
