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# how do i find the solution set for f(x)<0 and f(x) greater than or equl to 0 using a graph??

How do I find the solution set: for f(x)<0   and the solution set: f(x)greater than or equal to (symbol) 0 using a graph???

### 1 Answer by Expert Tutors

Michael K. | Math Tutor For High School Students and AdultsMath Tutor For High School Students and ...
4.9 4.9 (10 lesson ratings) (10)
2
You must remember that f(x)=y (value on the y-axis).
Well, you have an x-axis, and you look at where it intersects with the y-axis. At this point, y=0, and x=0.
As long as you move along the x-axis (to the left or to the right), the y-value will stay 0.
The x-axis is the key.
For every point above it, y>0.
Points where the graph of f(x) intersects with the x-axis: y=0.
Points below the x-axis: y<0.

y
^     y<0 for -1<x<1.3
`             |     y>=0 for x<=-1 and x>=1.3
`           |
`        2--                    `
`         |            `
`      1--        `
`       |        `
-----------------------------`---------|---|---|--------------------------> x
`  |   1  `2    3
|`  `