To find the sum of the interior angles of a nonagon, divide it up into triangles... There are seven triangles... Because the sum of the angles of each triangle is 180 degrees... We get
7 * 180 = 1260°
So, the sum of the interior angles of a nonagon is 1260 degrees.
72 sq in times 9 is 648 sq in
The key is to find the first term a(1) and the difference d.
in an arithmetic sequence, the nth term is the first term +(n-1)d
the firs three terms: a(1), a(1)+d, a(1)+2d
the next three terms: a(1)+3d, a(1)+4d, a(1)+5d,
a(1) + a(1)+d +a(1)+2d=108
a(1)+3d + a(1)+4d + a(1)+5d=183
subtract the first equation from the second equation: 9d=75, d=75/9=25/3
Plug d=25/3 in the first equation to find a(1): a(1)=83/3
the 11th term is: a(1)+(25/3)(11-1)=83/3 +250/3=111
Please double check my calculation. <span />
Answer:
A) 3; B) 1116 m²; C) 24 m³; D) 1/27
Step-by-step explanation:
A) Scale factor
The scale factor is the ratio of the heights of the two pyramids.
h₂/h₁ = 24/8 = 3
B) Surface area
The ratio of the surface areas is the square of the scale factor.
A₂/A₁ = 3²
A₂/124 = 9
A₂ = 124 × 9 = 1116 m²
The volume of the larger pyramid is 1116 m².
C) Volume
The ratio of the volumes is the cube of the scale factor.
V₂/V₁ = 3³
648/V₁ = 27
648 = 27V₁
V₁ = 648/27 = 24 m³
The volume of the smaller pyramid is 24 m³.
D) Volume ratio
V₁/V₂ = 24/648 = 1/27
The volume ratio is 1/27.
