SOLUTION: one question please when graphing a linear inequality how do we know if the inequality represents the area above the line.

Question 36114: one question please
when graphing a linear inequality how do we know if the inequality represents the area above the line.
Answer by ilana(307) (Show Source): You can put this solution on YOUR website!
2 ways:
If the inequality is of the form y>mx+b, it is the area above the line, if it is y(less than)mx+b, it is the area below. A method that will work regardless of the form of the inequality is to test points above or below. For example if I have 9x+3y>6, I draw the (dotted) line with slope -3 and y-intercept 2. I then test any point not on the line, so (0,0) is usually a nice simple choice. 9(0)+3(0)=0, which is not >6, so (0,0) is not in the shaded region. So the area above the line is shaded.
Note, if we wrote this inequality in slope-intercept form, we'd have y>-3x+2, so also by our first method the area above the line is shaded.
RELATED QUESTIONS
When graphing a linear inequality, how do you know if the inequality represents the area... (answered by rapaljer)

When graphing a linear inequality, how do you know if the inequality represents the area... (answered by Earlsdon)

When graphing a linear inequality, how do you know if the inequality represents the area... (answered by rapaljer)

When graphing a linear inequality, how do you know if the inequality represents the area... (answered by marcsam823)

When graphing a linear inequality how do you know if the inequality represents the area... (answered by mananth)

(3) When graphing a linear inequality, how do you know if the inequality represents the... (answered by Theo)

When graphing a linear inequality, how do you know if the inequality represents the area... (answered by Cintchr)

When graphing a linear inequality, how do you know if the inequality represents the area... (answered by stanbon)

1.) when solving a linear inequality, why do you always solve for y? 2.) when graphing (answered by longjonsilver)