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View Full Version : Graphing Linear inequality


CassHatesMath
Sep 15, 2010, 07:49 PM
5y-40<or equal to 8x

need to 2 set of cooridinates I know you use the straight line would love step by step on how to solve

Unknown008
Sep 15, 2010, 10:54 PM
5y - 40 \leq 8x

What you can do is convert into the form y = mx + c. This way, you'll be able to draw the line.

Then, think about points where y will be less than the 'mx + c'.

Is it okay?

morgaine300
Sep 17, 2010, 12:41 AM
This might be considered a bit cheating cause they may want you to think about it differently, but there's a quickie little test to know which direction of the line it goes.

Keep in mind that if a point makes your inequality a true statement, then all points on that same side of the line must also work. And if some point makes it not true, then all points on that side will also not work. So you only need test one point to know which way it's going.

And the easiest point to test is (0,0) cause it instantly wipes out 2 of 3 terms and you don't even really have to do any math.