The Maths Prof: Changing Subject of Formula EXAM QUESTIONS

This video contains a variety of exam questions on changing the subject of a formula (includes fractions, squaring, square rooting etc.). If you like, grab a pen, some paper and your calculator to have a go at some yourself! You can forward to the end of each example to check if your answer is correct... :-)
Answer to question 1 at 3:07
Answer to question 2 at 6:15
Answer to question 3 at 7:57
Answer to question 4 at 10:00
Answer to question 5 at 12:39
I hope you find the lesson useful! Subscribe to my RUclips channel to stay up to date with new uploads and follow me on Instagram @themathsprof for more maths! :-)

[@eugenewilliams8440]

I'm 62 years old. This is the first time someone has made math this clear !🙂👌

[@Sindhabadforever]

❤❤❤

[@thatboyany3512]

Maths Prof . I owe you 1 million dollars. I now understand the math than in class. Thanks a lot

[@agentxsz]

am i the only one who doesnt know how to thank her if she replied really i appreciate your work your the best your better than all teachers on earth !

[@mondesitahani7505]

Thanks a lot Maths Prof it really makes math so easy and understandable

[@adaugouzo3329]

😂😅

[@nehasingh-px2gw]

It deserves 2 million views or more than that ❤️

[@georgianmobster6761]

Thankful. This really helps me out

[@NotMarkKnopfler]

I'm 51 and now learning the maths that I was incapable of learning when I was at school! 👍

[@zoey3605]

i just found your channel and your videos are so helpful! thank you x1000000

[@the_.godfather_.1.0]

👏👏 thank you very much prof this really helps me all the way in southern Africa , Namibia

[@TheMathsProf]

So happy to hear that! 👍😁

[@jacquesdisles9833]

You're a great teacher. That would be tested in the final exam for twelfth grade. I will watch that video for more. Thank you for your wonderful tutorials and have a blessed day and stay safe. 😁😁😁🙌

[@musadem2554]

Thank you I don't understand it before but now is clear to me keep it up

[@silky6610]

Thank you. This helped me out

[@14bhirh_01]

THANK YOU!! It's very helpful

[@iangilbert4811]

You are a brilliant teacher. And you have a lovely smile :)

[@IcallDib]

true

[@tomsammons6480]

Shooting your shot Ian

[@iangilbert4811]

@@tomsammons6480 worth a try.

[@mnekidwell7048]

Wow. It's never been this easy. Thank you so much

[@rub8995]

Very very helpful , I have a math test and this was gold

[@patrickjoseph6929]

This lady is an excellent teacher

[@onsku6100]

Lovely!! It*s easy to watch this very clear teaching =) Br. Onni from Finland

[@dorisnyangu3014]

Thank you am following 😊

[@alialsuod9079]

Thanks Mam
Did pass exams beautifully bcz of you
Thanks

[@TheMathsProf]

Well done! 😄👏

[@srikanthsrini6873]

Really thanks I can understand very well

[@jamitjohnz252]

Thank you so much for helping me

[@kudakwashemitchell6882]

Woooooow you are a good teacher ....keep it up

[@kamabokogonpachiro6797]

You are le best teacher.

[@evexify_-5308]

Thank you so much

[@thevandesilva3436]

Your teaching is soooooooooo helpful...I really love your teaching !

[@TheMathsProf]

I'm so happy it helped! 🙌

[@ha7classic127]

@@TheMathsProf why have you stopped you"re such a wonderful teacher

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Thank you 🌹

[@mayashura4829]

You’re amazing

[@vinesta]

Thank you for the help !!!!

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The best youtube teacher 👐👐👐👐👐👐

[@hasanyousaf6746]

Have you heard of freesciencelessons?

[@hassansingano1150]

Thanks

[@babe2016]

your lessons are really easy to understand

[@TheMathsProf]

So pleased you think so ☺️👍

[@abdullahisane]

Thank you teacher . this helped me a lot 😢❤❤

[@TheMathsProf]

I'm so glad!:)

[@MarciaArleneDebra]

The ample variety of questions adequately illustrates the use of changing the subject of the formula with different operations, and provides cognitive flexibility in the use of the technique.

[@furgansiyahov7296]

Which grade is this for

[@stalli4life]

Thank you for the help👏🏻

[@daeshafindley796]

for that last question i change it up a little and got the same anwser

[@asmaasaadsaad3290]

Make y the subject of 8-2y+5x=0
Do we add or subtract the eight to cancel it out

[@Mocha_Moon_011]

Thank you🤗

[@TheMathsProf]

You’re welcome 😊

[@solomonappiagyei7322]

you are the bestttttttt

[@heriakleguzaye7935]

ma favourite teacher

[@otienoedgardavis4550]

Applause to the teacher 👏👏👏✔️💯💯

[@tomandjerry2069]

The third formula to make b the subject i did differently i just presumed that root a sqaured plus b squared would equal a+b.
My answer was just the exact square root of yours c-a=b

[@parijat8166]

that's not how it works. You can't make the square root of a2+b2 = a+b. The square root is for the EQUATION'S ANSWER, not the variables itself. It's a rule in algebra. Therefore your answer is wrong and is not the same as hers.

[@bradleythomas214]

Thank you.

[@TheMathsProf]

You're welcome! 😊

[@habibaelhadad1000]

Thank u

[@trishsamson4184]

Woooooow this is sooo greeeeat😄🤩

[@ZachDrake5960]

I did notice a pro and a con with your first example.
PRO : With this example you showed that quadratic equations, where y is a quadratic function of x, can be rearranged. The key is to start with converting the quadratic from standard form to vertex form. In standard form, quadratics have x terms with different powers, making it impossible to isolate x. In vertex form, it is written with one x value going through an addition/subtraction, then squared, and multiplied by a number, and then adding/subtracting a number. The fact that there is one x value listed in vertex form means there is no conflict of powers of x like in standard form, now making it possible to isolate x.
CON : The one gripe I had is the fact that when you got rid of the square by square rooting, you forgot to mention that it can be a positive root and/or a negative root, since squaring any real number, positive or negative, always gives a positive. So, the answer is 4 + or - that square root, with 4 out in front so as to show it is not inside the root. The same goes for the pythagorean theorem example. I figured this out when I tried graphing similar examples.

[@user-le3fs1us8l]

Hi MathProf how would you make t the subject of the formula in the S=ut+at^2 expression

[@KarimatouJallow-km6yg]

I like how u teach it makes😃 me understand more 🥰

[@KarimatouJallow-km6yg]

But I want subject of the formula where u have pie r square

[@clems6989]

You truly are wonderful......

[@furthermoore1863]

the best

[@joseph_donovan]

Indubitably! Love it. Thank you.

[@rizzoli7]

lmao stfu

[@yasminelsawefy]

Amazing especially for the British cirrculum

[@solomonappiagyei7322]

i finally understand love you so muuch and keep up the good teaching

[@myslenienieboli9512]

Thank you very much!

[@hz6612]

5:40 please can anyone explain me why she divided by t² instead of dividing by square root of t since the square root is the inverse of power ????

[@urlocalyoutuber6700]

This topic was my nightmare, but you made it seem so easy. Thank you so much

[@abdulazizalghfily7420]

Thank you, your better than my math teacher

[@tramhicks1215]

I understand some.

[@shekhar7747]

Lots of Thank u🙏

[@cardiminaj9240]

You so much help 😊🖒🖒🖒🖒

[@BlessGodMinistry]

Appreciate the help thanks so much God bless you

[@jameswilson5980]

So much easy than the Nigerian way of solving subject of formula

[@cholo7198]

dont u cancel out the sqrt and square of c - a?

[@SyoopGames]

Hello Teacher, i got a question. (4:46) Now can i not get rid of the 1/2? Or I need to?

[@joliehany7942]

Could you please help me with this
d=a(2+3b) and make a the subject of formula

[@lizsa3145]

Wow! ok so home educating my daughter for IGCSE's...she asks me all the time..'why on earth do they need to learn these formula's?!'....I ask that myself, unbelievably difficult!..

[@kabirmishra8432]

I have a question. At 7:05 you say that to cancel out the a^2 we need to do subtract a^2 from a^2, but then when you cancel out the b^2 you square root. How am I meant to know when to subtract and when to square root.
Someone in the comments please help

[@toluwanimiosuntoyinbo9336]

She did not subtract b² cos 'b' was the subject so you can't cancel it out. If 'a' was the subject, you use the square root instead of subtracting

[@raphaelowen478]

Thanks....You have helped me out....

[@tennehmoina2827]

That is the formula for displacement or distance

[@user-nd2qj9ey7i]

"have fun" yeah righ

[@sa_gaming_pro6517]

A=p(1+i) raises to 6

[@KarimatouJallow-km6yg]

I want subject of the formula where u have pie r square

[@Art2020]

I would also like to you teach me computer pseudo code topic

[@shahidarazak3402]

Thanks a lot, I am going to teach how to change the formula of the subject and I just learn how.

[@onsku6100]

These videos are very helpful when you changing subject of Formula, but do you coming any physics or do you know any good sites with learnig these Formula EXAM QUESTIONS ? THAANKS =)

[@klau3502]

One question ....I'm from Albania so (sorry if i make any problem while writing).. I wanted to ask u when do we use the formula (a+b)2= a2+2ab+b2 (2 is Squared ) thank u in advance...waiting for your reply

[@TheMathsProf]

Expanding brackets (a+b)² = (a+b)(a+b) = a²+2ab+b² 😊

[@PIKACHU-hf7sc]

I wish you are my teacher

[@fazzynone1]

This is extended, these are a bit difficult compared to what I studied and to what I'm preparing for, which is core.

[@TiberiusStorm]

For the second question, why wouldn't you divide "ut" since they are multiplied? Instead you subtracted them.

[@Astronomynatureandmusic]

Like you say, UT is U multiplied by T. In algebra you can see that as one "unit" called UT. You are able to add or subtract by such a unit.

[@ANONYMOUSUSER54]

She is bomb thankful for your videos

[@muhdaabaa]

Opposites sign of:
• + » -
• - »+
• × » ÷
• square » square root

[@mosesutoni466]

❣

[@ayenstevens]

What if they say make X the subject of the formula (x+n)²=x²+5

[@user-le3fs1us8l]

Yeah

[@AnthonySusanna]

😊

[@IslamicNationChannel__Somali]

What I felt this as topic of form 1

[@tomandjerry2069]

Ur letter a's look like a 2 and thats cool

[@horriblehater]

no its not

[@nabihaasif8227]

It was very helpful.
Can you make a video under the topic USING THE BALANCING METHOD

[@mubassilhafeez6890]

tomorrow is my exam, Thanks!

[@georgesadler7830]

Miss Math Prof, in problem one, you are missing a plus and minus sign in front of the square root of y-6 and also a plus and minus sign in front of the square root of C -A^2. Please correct these errors in the video.

[@nutty239]

Of course. I know

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Marry me.

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I love you

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You are too much

[@antonior1908]

I like your teaching ,but your British accent is about taking away my interest of your lecture. I am most comfortable with the Canadian accent ,thanks anyway

[@14bhirh_01]

THANK YOU!! It's very helpful

[@paulmorrey733]

Thanks