need help graphing and finding points  TOPIC_SOLVED

Simple patterns, variables, the order of operations, simplification, evaluation, linear equations and graphs, etc.

need help graphing and finding points

Postby bbb95 on Wed May 13, 2009 2:08 am

trying to figure out graphing on -4(2x+y)=or grater than -8
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Re: need help graphing and finding points  TOPIC_SOLVED

Postby Martingale on Wed May 13, 2009 3:00 am

bbb95 wrote:trying to figure out graphing on -4(2x+y)=or grater than -8



Are you wanting to graph

try looking at
Graphing Linear Inequalities
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Re: need help graphing and finding points

Postby sdbielz on Mon Jul 20, 2009 2:49 pm

-4(2x+y)=or grater than -8 [distribute]

-8x-4y =or> -8 [isolate the y]

-4y=-8+8x [divide both sides by the -4, and don't forget to flip the inequality sign bc you divided by a negative number]

y <= 2-4x

now just find the intercepts; at which point does x=0, and y=0

(0,2) (1/2,0)

next, we find the slope, which is simply the change in Y over the change in X. (Y-y/X-x)

(2-0)/(0-.5)====2/-.5

we simplify this by 'unreducing'....ironically. 4/-1.

so the slope is negative (drops from left to right) and raises 4 units for every 1 unit it shifts left.

I would use this concept to plug in see if y<=-2 when x is 1.... kinda to check my work. and it appears to be correct.

now you have three points to plot... (0,2) (.5/0) and (1,-2).

Draw a SOLID (bc its <=) line through the points, and shade in everything below it...bc its less than or equal to.

hope this helped...
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Re: need help graphing and finding points

Postby Tenzin on Thu Aug 06, 2009 12:43 pm

bbb95 wrote:trying to figure out graphing on -4(2x+y)=or grater than -8
metooineed help with this :confused:
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Postby stapel_eliz on Thu Aug 06, 2009 2:59 pm

If the lesson-link and the explanation and solution have left you still lost, then I'm afraid you need more help than we can here provide. Sorry! :oops:

Please give serious thought to hiring a qualified local tutor, and setting aside a few hours a week (an hour or two a day would be best) for concentrated study sessions. By working with you face-to-face, your tutor can find the gaps in your knowledge which are preventing you from being able to learn the new material, providing individualized instruction to help you get caught up. :idea:

My best wishes to you in your studies! :D
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