Solving Algebraic Inequalities

We've seen lots of equations, which are constructs that equate two things, but there are also inequalities, which state that two things are not equal, but rather that one is greater than or less than the other. We can solve this just like equations, but there are one or two little differences that we have to go over. Check it out!
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[@aoudau7451]

he do be vibibing in the intro doe

[@priyasingh_rajput]

It's been two years for me to study maths but now I have to prepare for entrance exam and this playlist helps me a lot :)

[@AngelicBambi]

Oh em gee I'm also watching this video while preparing to do an entrance exam!! Did you get in?

[@orbon60fps75]

the professor dave explains in the intro gives me chills 😂🤣

[@justbbricks]

“I fear no man, but that thing... Professor Dave... it scares me.”

[@f1shy27]

Lol 😂, Love that meme!

[@Miascorpion]

@@f1shy27🤣🤣🤣😂😂

[@f1shy27]

@@Miascorpion I didnt even remember i commented this. wow 2 years ago

[@Miascorpion]

@@f1shy27 yeaaaaa time goes very fast((:

[@matthewcalleros7249]

thanks a lot ive been having a lot of trouble with inequalities and was really stressed out but this vid helped ty

[@tammymaloney4816]

Very helpful! Thanks

[@jacklinemmaduagwu8037]

Good job in teaching inequalities,👍DAVE

[@deckkorriyow8241]

thanks man it really helped .

[@Decco6306]

Dear dave, Hi. KipperKlank. (Oh yeah, you have no idea how fun it is to rediscover all the shit in math I never paid attention to in middle school/high school. Thank you.)

[@aidangreaves7188]

why curse? are you a christian?

[@Decco6306]

@@aidangreaves7188 Why complain? Are you upset?

[@Decco6306]

@That Multistan I like potatoes and green beans with my roast thanks.

[@lanzibangli1259]

a > b = b < a

[@ParmelionHoughton]

Last equation has two ways to solve. One way gives you 6

[@Williamfurno962]

love the intro

[@samuela1918]

How can an positive X be less than an negative number?

[@xoash9641]

thanks❤

[@mikeymikey3085]

Hi, Is it true that any number has decimal point ? If yes how can we prove it ? Thanks

[@ramblingsFromJim]

If there is no decimal point present, it is assumed to be at the very right of the number (ie, 34 is actually 34.0)

[@SmithJohn-kf7jq]

Is it okay if you write 3 is less than x for the last equation? Because x was on the right side, that's what I got, and forgot to put x on the left. Since it's still the same answer but written differently, would it be okay? or does x always have to be on the left side?

[@fatehero4750]

it's the same

[@cmak_1200]

I just did the same thing

[@ermikaa1]

@@cmak_1200me also

[@kaiserkonok]

You must do every exercises given in the video to test you that you have learned it properly

[@ajmalabidinnur2173]

OH MY GOD! WHAT IS NOT IN THIS CHANNEL?!

[@ninisinterlude]

Can someone please answer this before I submit or just please answer? How does 3x divided by 3 equal zero?

[@ProfessorDaveExplains]

It doesn't, it equals x.

[@ninisinterlude]

@@ProfessorDaveExplains thanks

[@caronfernandes4625]

If x= -1 then the answer is zero

[@trinitycat1723]

that intro though. "NOICE!"

[@caronfernandes4625]

What into?

[@pista69420]

the question 3-x > 17 can also be answered as -x > -14

[@ultranoob9591]

No it can only be answered in 2 ways one is x14 😊

[@dontstealmydiamondsv3156]

It certainly is very easy to make mistakes. Practice makes perfect I suppose.

[@justbbricks]

Maybe you just can’t do it

[@itszyzzbrah4469]

@@justbbricks nah, its all about practice and basic understanding..

[@muhammadsalam-dev]

If the equation is (3x-8)/-2 < 5 then 3x-8 > 5 * -2 ?

[@mr.salph9871]

Yes, it would be solved like this: 3x-8>5*-2 = 3x-8>-10 3x-8+8 > -10+8 = 3x > -2 x = -2/3

[@switchedl4nes]

The intro has me shook O_O

[@caronfernandes4625]

What is in the intro?

[@codexcodexcodex]

@@caronfernandes4625 I don't knoww

[@user-em5jw2sg8l]

I am not getting your last videos

[@ljr6490]

Holy crap I didn't believe it was that simple

[@rubinamujahidah1040]

*Just one question* Why are we taking (-10) why can't we take positive no. Instead 🤔 In .... *-x > 6* & *x < -6*

[@brandish_0003]

because it isn't correct, put the number in and see the result

[@tzaaaltee]

Someone explain the last equation

[@a.v.w.6453]

If 2X + 9 is less than 4X + 3 , then naturally 4X + 3 is greater than 2X + 9. 4X + 3 > 2X + 9 is just a different way to express X + X + X + X + 3 > X + X + 9. We can isolate the 9 by subtracting 2X from both sides. This leaves us with 2X + 3 > 9. The next step is to cancel out the 3 by subtracting it from both sides. Now we have 2X > 6. Dividing 2X by 2 gives us X, and dividing 6 by 2 gives us 3. In conclusion, X > 3.

[@rohithrajstudies2136]

in the last problem why did the sign changed were X

[@TheOtherKneeGrowGuy]

Going for the process to help explain, 2x +9 < 4x +3, Going by Pemdas magic we subtract the +3 frist, 2x +6 < 4x, then we subtract 2x from both sides, +6 < 2x, then we divide both side by 2, 3 < x, however now we filp the entire equation as we like to read it like that, making our answer be × > 3, hope this helps! You probably already figured it out but I'm just leaving this here for others.

[@hughjanuz4343]

got confused why their sign is flipped when the value of x, is just x in comprehension. what did I miss?

[@carl8790]

When a variable is negative (-x), you'll have to multiple or divide by -1 to get x. When multiplying or dividing negative variables, the sign must be flipped.

[@happyjohn1656]

Embarrassed coming here as a college student 3:54 AM (yep!) 3/29/2022

[@durveshsonar7846]

Can someone explain 2x +9 < 4x +3 Why sign changed

[@durveshsonar7846]

so nice of you.. It's help me a lot

[@Tusharplays69]

I solved it like this: 2x+9

[@davidbalta6973]

Nice

[@Lord_Marquaad]

Letters are math too, Letters have rights, Letters life matters!

[@fof3904]

Sir is it allowed to move numbers and variables from left side to the right side in this lesson?

[@lanzibangli1259]

yes. but if you do that, flip the signs: a > b is the same thing as b < a notice that the sign is flipped. examples: x < 5 Also means 5 > x 9 > 3 Also means 3 < 9

[@Belmont1714]

​@@lanzibangli1259I couldn't get the third one, can you help?

[@mdf1259]

2x+9

[@arpittripathi9472]

Step 1: Subtract both side with 3. Step 2: Subtract both side with 2x. Step 3: Divide both side with 2 and you will get 33(unnecessary step).

[@TheSnowyOwl-zg2ck]

​@@arpittripathi9472 So, since it is an unnecessary step, why is it there?

[@lanzibangli1259]

@@TheSnowyOwl-zg2ck a > b Also means b < a 3 > 2 means 2 < 3 Usually it doesn't matter, but it's easier to read if the variable is on the left side. So if you get 3 < x you can just say x > 3. 3 is smaller than x x is bigger than 3 All means the same thing. Also, notice how equalities don't have this issue: a = b means b = a the sign is symmetrical.

[@UseHerName000]

@@arpittripathi9472 tysm

[@sauravjagtap7105]

Sir please explain Transistor and how it work

[@Decco6306]

No.

[@tahana4709]

@@Decco6306 bruh

[@rubinamujahidah1040]

*I wish you were my teacher* 🥰 😭 😭 😭 😭

[@SCRKT007]

3x + 2 < 20 3x + 2 - 2 < 20 -2 3x < 18 3x/3 < 18/3 x > 6, shouldn't the symbol be "greater than" because we flip it from doing a division?

[@tanishkasahoopatia2923]

No, sign won't be flipped as it is a positive number not a negative number. Remember that " sign gets flipped only when negative number is mulplying or dividing"

[@Wildasf1]

Guys can we create a group chat for math and share exercises with each other

[@twrxzq]

exactly!! 😭 coz i need more equations that i could practice on T-T for the first time in my life, i find mathematics fun.🤞🏻

[@twrxzq]

if u made one, pls tell me🙏🏻

[@jaihindsharma7134]

😊😊😊😊😊😊

[@mamadwali4278]

❤❤❤

[@TANGUANXU]

he looks kinda like jesus

[@zeenokbeenok]

lmao

[@pobletekinze6537]

x-4>3 x>7 3x+2

[@pobletekinze6537]

3-x>17 x>-14

[@Angel-fz2kz]

yurr

[@justbbricks]

my dude are you alright

[@justbbricks]

help I didn’t type that

[@silentseashelllistener3818]

@@justbbricks my dude are you alright

[@justbbricks]

@@silentseashelllistener3818 my girlfriend made me type that

[@silentseashelllistener3818]

@@justbbricks my ego made me type that

[@droidgamer4049]

I love the video it's helping me

[@ericnlopezpagan2699]

Im a bit confused by the last one. I got it right but re-doing the math to add a value to x>3 the whole thing just fails... Please correct what im doing wrong. x=2 2(2)+9

[@ratasan8928]

Hi Eric. The result says, but you use x>3 x=2 That's the mistake, the solution requires it to be bigger than 3, and you're using 2. I speak Spanish as well, if you need more help, I can gladly help you in Spanish as well

[@a.v.w.6453]

I know it's been several months but let me walk you through how I did it: If 2X + 9 is less than 4X + 3 , then naturally 4X + 3 is greater than 2X + 9. 4X + 3 > 2X + 9 is just a different way to express X + X + X + X + 3 > X + X + 9. We can isolate the 9 by subtracting 2X from both sides. This leaves us with 2X + 3 > 9. The next step is to cancel out the 3 by subtracting it from both sides. Now we have 2X > 6. Dividing 2X by 2 gives us X, and dividing 6 by 2 gives us 3. In conclusion, X > 3. I hope this is helpful.

[@tom.5033]

@@a.v.w.6453 thanks man, i really appreciate it.

[@ispeakwhenimallowedto..3582]

@@a.v.w.6453 and why not let the 3 as it is and find negative value x -3...... without changing the row of values? i mean SHOULD BE LIKE this: 2x+9>3 why u write it reverse? 2x+3>9 changing the core comparison value...

[@a.v.w.6453]

@@ispeakwhenimallowedto..3582 Another way to get the answer is by subtracting 3 from both sides first, which leaves 2X+6

[@mias1240]

you just confused me lol

[@LC-yv9ey]

x > 7 x < 6 x < -14

[@pingu7075]

"x < -14"??? That makes no sense. If x=5 then 5 < -14???

[@TheOtherKneeGrowGuy]

There's 2 way to answer that equation, 3 - x > 17, going by Pemdas magic, Subtract 3 from both sides, -x > 14 that's one of our answers, or we could multiple both sides by -1 to make x < -14, since 14 wasn't it became negative because of the -1 multiple, and two negatives makes a positive that's why -x became positive when it got multipled. Hope this helps!

[@Michelle-ob2un]

Speak slower next time please

[@claudioderobbio9316]

You can slow the video

[@LoveTheUmmah822]

TOO FAST LMAAO CALM DOWN