robpez!

Could some one show me the easiest way to graph linear inequalities like this:

. . 2x + 5y > -10

Also what if the problem has two inequalities for one question?

As the Captain suggested, graph the __equality__ (line).

The line: .2x + 5y .= .-10 .has intercepts (-5,0) and (0,-2) ******

Graph this line . . . use a dotted line since it is **not** included in the solution.

Solve the inequality for y (carefully!)

. . 2x + 5y .> .-10

. . . . . .5y .> .-2x - 10

. . . . . . .y .> .(-2/5)x - 2

Since the inequality is **>**, shade the region __above__ the line.

. . (If it was **<**, shade __below__ the line.)

The graph should look like this: Code:

::::::::::::::::|::::::::::::::::::
::::::::::::::::|::::::::::::::::::
o:::::::::::::::|::::::::::::::::::
- - - o:-:-:-:-:-:+:-:-:-:-:-:-:-:-:- -
-5 o:::::::|::::::::::::::::
o:::|::::::::::::::
-2o::::::::::::
| o::::::

****** With the equation: .2x + 5y .= .-10, the intercepts are easily found.

I perform what I call "Thumb Algebra".

To find the *x*-intercept, let *y = 0.*

. . Cover *5y* with your thumb and solve: .2x = -10 . → . x = -5

To find the *y*-intercept, let *x = 0.*

. . Cover *2x* with your thumb and solve: .5y = -10 . → . y = -2

Got it?