Seudónimo Seudónimo
  • 02-07-2017
  • Mathematics
contestada

A polygon has 27 diagonal. How many sides does it have?

Respuesta :

Banabanana
Banabanana Banabanana
  • 02-07-2017
[tex] \frac{n(n-3)}{2}=d \ \ \ \ \ \text{[n - number of sides, d - number of diagonals] } \\ \\ \frac{n(n-3)}{2}=27 \\ n(n-3)=27*2 \\ n^2-3n = 54 \\ n^2-3n-54=0 \\ discriminant=(-3)^2-4*1*(-54)=225 \\ n_1= \frac{3- \sqrt{225} }{2}= \frac{3-15}{2} = -6 \ \ \ \O \\ n_2= \frac{3+ \sqrt{225} }{2}= \frac{3+15}{2} = 9[/tex]

The polygon has 9 sides.
Answer Link

Otras preguntas

What force is needed to accelerate a child on a sled (total mass = 65.0 kg ) at 1.25 m/s2?
Tariffs differ from taxes because tariffs are what?
What is the common difference, the general term equation, and the 12th term of the arithmetic sequence? Hint: a_n=a_1+d(n-1) , where a_1 is the first term an
the information in this chart best illustrates the biological concept that
Why is taking notes while reading helpful
Why did John Adams agree to defend Captain Preston and the British soldiers?
simplify by collecting like terms: 8h-3h(+3k)
Describe the relationship between goods services and consumers
What is a number that when you multiply it by 6 and you subtract 4 from the product, you get 50?
When fritz drives to work his trip takes 30 ​minutes, but when he takes the train it takes 20 minutes. find the distance fritz travels to work if the train tr