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If all possible diagonals formed are 740 then find the number of sides​

User Dean Hill
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1 Answer

6 votes

Answer:

40 sides

Explanation:

The number os sides can be calculated using


(n(n-3))/(2) = d ( n is number of sides and d number of diagonals )

Here d = 740 , then


(n(n-3))/(2) = 740 ( multiply both sides by 2 )

n(n - 3) = 1480

n² - 3n = 1480 ( subtract 1480 from both sides )

n² - 3n - 1480 = 0 ← in standard form

(n - 40)(n + 37) = 0 ← in factored form

Equate each factor to zero and solve for n

n - 40 = 0 ⇒ n = 40

n + 37 = 0 ⇒ n = - 37

A polygon cannot have a negative number of sides.

Then number of sides is 40

User Paula Kristin
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