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Solving Inequalities Videos 8 videos
Solving inequalities using blob fish? Yes, please!
Meet the Shmooples. They live on Planet Frisbee, where there is a lot of inequality. Of the arm and Starburst variety, mostly.
Do you have a date for the prom yet? No? Have you tried impressing your crush with your inequality solving skillz? Well, then, we don't know why yo...
ACT Math 5.3 Coordinate Geometry 436 Views
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Description:
ACT Math: Coordinate Geometry Drill 5, Problem 3. Graph the inequality.
Transcript
- 00:02
Here's another shmoop du jour...
- 00:05
Graph the inequality -4 ≤ -2x < 6.
- 00:10
And here are your potential answers...
- 00:14
As with all of these kinds of problems, there
- 00:17
are really two inequalities here...the first is: negative 4 is less than or equal to negative 2x.
Full Transcript
- 00:23
To isolate x we need to divide both sides by negative 2...
- 00:23
To isolate x we need to divide both sides by negative 2 and… a red light should be
- 00:27
Whenever we divide or multiply an inequality by a negative, we have to flip the sideways
- 00:31
ice cream cone once
- 00:32
around...x is less than or equal to 2.
- 00:35
Well, we have a starting point.
- 00:37
On our number line we mark the 2... and since it's less than OR equal to, it means that
- 00:43
the dot has to be filled in...
- 00:46
So B and C don't work... and neither does A, which starts at 3 rather than 2.
- 00:50
We know that x is LESS than 2, meaning that it's gonna live somewhere
- 00:54
over here...
- 00:55
The only one left that might work is D... but just to be sure let's check out the 2nd
- 00:59
part of the equation.
- 01:00
We have negative 2x is less than 6... Divide both sides by negative 2, flip around
- 01:06
the sideways ice cream cone thingy...
- 01:09
...and we have x is greater than negative 3.
- 01:11
So yep, the answer is indeed D.
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You don't want to leave a bunch of unsolved rational equations sitting around.
Solving inequalities using blob fish? Yes, please!