1. what is a hollow circle ?
2. what is a perfect Circle ?
3.Heron's formula

2. the collection of all points in a plane that are the same distance from a central point is called a perfect circle.

1) The hollow circle is one which is empty from inside

2) perfect circle has infinite sides and points which are at equal distance from the centre

3) Heron's formula = Root S ( s- a) (s - b) ( s - c)

step-by-step explanation:

x= -3 and

step-by-step explanation:

to find the roots of a cubic, use division or factoring to find the factors then set equal to 0. as this is a difference of cubes, it factors into

where a is the cube root of .

here   this is 27 and the cube root of 27 is 3. so we write using the form:

.

set each factor to 0 and solve for x.

x-3=0

x=3

the quadratic expression does not factor and must be solved using the quadratic formula.

where a = 1, b=3, and c=9

this cubic has two complex roots.