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.

the length of o'p' is .

step-by-step explanation:

it is given that the quadrilateral m'n'o'p' is the image of quadrilateral mnop after dilation.

the center of dilation is origin and the scale factor is 1.5.

in dilation the image and preimge are similar figures. it means the sides of image and preimage are proportional.

the scale factor is defined as

the scale factor is 1.5.

multiply both sides by op.

note: if the value of op is given, then multiply the value of op with 1.5 to get the length of side o'p'.

therefore length of o'p' is .