A number line is usually used for this purpose.
http://wiki.answers.com/Q/What_are_the_examples_Di...

1. Factor the equation. For instance, you can rewrite the equation 2x^3+3x^2+2x+3=0 as x^2*2x+3) + 1(2x+3)0, then as (x^2+1)2x+3)0. 2. Obtain the roots of the equation. When you set
http://www.ehow.com/how_8252240_solveequationsre...

You are talking about a real number diagram as if it were the schematics of an electronic gadget. there is not much to it. Just a few circles or enclosures embedded into one another
http://www.fixya.com/support/t12994589draw_schema...

( ¦rēl ′nəm·bər ′sis·təm ) (mathematics) The unique (to within isomorphism) complete ordered field; the field of real numbers.
http://www.answers.com/topic/realnumbersystem
