One way to think of this is to join all the vertices of the polygon to a single point call this point X. For a n-sided poygon, you now have n triangles. The sum of all the angles of each triangle is 180 degrees. So all the angles of all the n triangles add to n*180 degrees.
But, this sum includes all the angles around the point X and these add to 360 = 2*180 degrees. These need to be taken away. So (n-2)*180 degrees.
Formula: 0.5*(n2-3n) where n is the number of sides
The sum of the first 10 positive integers, using the formula N1 + (N1 + 1) + ... + N2 = N2 * (N2 + 1) / 2 - (N1 - 1) * N1 / 2 is: 55
The formula can be written, with "n" representing a number or value, as n2 or n X n.
tn = n2
1/2*(n2-3n) = number of diagonals Rearranging the formula: n2-3n-(2*diagonals) = 0 Solve as a quadratic equation and taking the positive value of n as the number of sides.
The chemical formula for helium is He, and the chemical formula for nitrogen is N2.
Formula: N2
Formula: N2
Its Dinitrogen
N2
Formula: N2
n2
N2
N2
The chemical formula of liquid nitrogen is N2, meaning it consists of two nitrogen atoms covalently bonded together.
The formula for the synthesis of ammonia from diatomic nitrogen and hydrogen is: N2+3H2-->2NH3
The chemical formula for liquid nitrogen is N2, which means it is composed of nitrogen molecules, each consisting of two nitrogen atoms bonded together.