The sum of the interior angles of a polygon is 9x². If x is 3 greater than the number of side of the polygon, how many sides does the polygon have?

17

Step-by-step explanation:

This is a very neat problem -- for teachers.

Let the number of sides = y

The sum of the interior angles is 180*(y - 2)

We are told that this sum equals 9x^2

So far the equation is

(y - 2)*180 = 9x^2                   Divide both sides by 9

(y - 2)*20 = x^2                       Remove the brackets on the left.

20*y - 40 = x^2

We need another fact. We get that from the statement that x is three greater than the number of sides (y). Therefore y = x - 3

20*(x - 3) - 40 = x^2

20x - 60 - 40 = x^2       Combine like terms on the left

20x - 100 = x^2             Bring the left side to the right side.

0 = x^2 - 20x + 100      You have a quadratic.

a = 1

b = - 20

c = 100

When you solve the quadratic equation, you get

x = 20

Therefore the number of sides is 17.

i think it is c, not positive though

step-by-step explanation:

answer: at first, in 1635, the evening meetings had been just for women . .

what relationship between ideas is shown in the text above?

question 1 options:

location of events

similarity of events

timing of events

examples of an idea

step-by-step explanation: