Can You Calculate the Area of a Triangle that is Inside of a Square? | Step-by-Step Tutorial

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  • Опубліковано 16 гру 2024

КОМЕНТАРІ • 74

  • @elisenvlog4210
    @elisenvlog4210 3 роки тому +9

    Very nice sharing, sending my full support

    • @PreMath
      @PreMath  3 роки тому +4

      So nice of you Elisen! You are awesome 👍 I'm glad you liked it! Please keep sharing premath channel with your family and friends. Take care dear and stay blessed😃

  • @Ramkabharosa
    @Ramkabharosa 3 роки тому +8

    Add the points G & H directly opposite E & F; & let J be the intersection of the lines EG & FH. This will give us a partition of ABCD into
    four rectangles. Let area(CGJH)= z. Then area(AEJF)=10, area (DFJG)=6-z, area(BEJH)=8-z, and z

  • @mahendrashedmake4478
    @mahendrashedmake4478 3 роки тому +1

    I am from india and not all but some people thinks that we can't understand the english of the foreigners but we can understand and i like to watch your videos to learn new things

    • @PreMath
      @PreMath  3 роки тому +1

      Dear Mahendra, you guys are very smart and hard working people! You are the best 👍
      Keep smiling😊

  • @patrickchapman8583
    @patrickchapman8583 3 роки тому +16

    I enjoyed the video, but I think the reasoning for why one possible value of x^2 was rejected could have been clearer. At that point, there wasn't a clear criterion for why one value should be accepted over the other. Perhaps the video should have started with that the area of the square is x^2, and that the area of the triangle EFC would be the area of the square minus the sum of the areas of the other three triangles, and thus x^2-12. Then go into finding the sides of the triangles in terms of X. Then when you get to the value of x^2 you have a reason to reject the value that is less than 12 because that would make the area of triangle EFC negative, and you can't have a negative value for the area.

    • @PreMath
      @PreMath  3 роки тому +4

      Dear Patrick, thanks for your nice feedback. Please keep giving your honest feedback. That would help us to server our audience much better.
      Actually, u=x^2, and X^2 is the area of the square. If I pick u=2.2 value => X^2 = 2.2 = the area of the square. And that's not possible because the square is way bigger than 2.2.
      You are awesome 👍 Take care dear and stay blessed😃

    • @jamesb2675
      @jamesb2675 3 роки тому +6

      Patrick's comments are exactly right. I didn't follow in my first viewing why 2.2 should be rejected. But more important than that, as Patrick also noted, the solution should start not with "Step 1," but rather with a logical explanation of the strategy to be used to solve the problem. In this case, "we're going to find the area of the internal triangle by first finding the area of the square and then subtracting the total area of the three triangles for which the areas are given." "The area of the square, X>2, should be a hint that this is a quadratic equation problem, and one of the first steps will be to express each segment of the sides of the square in terms of a single variable, X." It is not always easy to communicate these strategies, but I think therein lies the challenge for the student/teacher (and thus the learning opportunity), more so than in the algebraic manipulations of the solution steps (though those are important too). You're doing a great job, Professor; keep up the good work in getting our youth excited about math. 👍

    • @PreMath
      @PreMath  3 роки тому +4

      @@jamesb2675 Thanks my friend for your kind feedback. I really appreciate that. This feedback would help me shaping future videos. Thank you so much for your continued love and support. Take care dear and stay blessed😃 You are awesome. Keep smiling😊

  • @restablex
    @restablex 3 роки тому +3

    General case for all rectangles (not only squares)...
    Having: (Y)ellow; (B)lue;(G)reen;(W)hite.
    W = √( (Y+B+G)^2 - 4(B)(Y) )
    Then
    W = √( (5+3+4)^2 - 4(3)(4) ) = √96 =4√6

    • @davidbrisbane7206
      @davidbrisbane7206 3 роки тому

      Where did you find this formula?

    • @restablex
      @restablex 3 роки тому +1

      @@davidbrisbane7206
      I solved this problem...
      ua-cam.com/video/6K_j4Cj7mVo/v-deo.html
      Got the same answer using another method but the original is ok.

    • @davidbrisbane7206
      @davidbrisbane7206 3 роки тому +2

      @@restablex
      Great. Thanks. MindYourDecisons demonstrates how to derive the formula very simply.

  • @shadrana1
    @shadrana1 2 роки тому

    At 0:37,
    Let AB=BC=CD=DA=t say
    From the orange triangle we worked out DF=a say
    From the blue triangle we worked out EB=4a/3
    From the green triangle we worked out FA*AE/2=5
    (t-a)(t-4a/3)=10
    a=6/t and substitute into above equation,
    That ended up as a quadratic in t^2,
    (t^2)^2-24(t)^2-48=0
    We worked out the area of ABCD =t^2 =12+4sqrt6
    Then subtract the area of the three triangles of 3+4+5 from area ABCD
    =12+4sqrt6-12
    =4sqrt6 square units.
    Same as last time with different symbols used.

  • @hefenywaiters7965
    @hefenywaiters7965 3 роки тому

    Thank u for teaching or explaining in simple ways.. You take the time to break things down so that we understand the basic and the details of a certain problem... Thank u for being patient and clear..

  • @kasnarfburns210
    @kasnarfburns210 3 роки тому +3

    When you're venturing into that quadratic formula, you know there's A LOT of book keeping to do!!

    • @JLvatron
      @JLvatron 3 роки тому

      Too much fo me!

  • @theoyanto
    @theoyanto Рік тому

    Wow, a phenomenally phenomenal phenomena, a work of absolute algebraic artistry.
    And... no way did I do this one ,
    but just so enlightening, particularly like the last bit using "u", that is new knowledge for me, thank you 🤓

  • @j.r.1210
    @j.r.1210 3 роки тому +2

    It's always satisfying when you work through one of these elaborate problems, then watch the video and see the equations you just wrote down on paper start appearing on the screen. :) Thanks.

    • @PreMath
      @PreMath  3 роки тому +1

      So nice of you J R! You are awesome 👍 I'm glad you liked it! Take care dear and stay blessed😃

  • @antoniocoburn5265
    @antoniocoburn5265 3 роки тому +2

    Thank you for the info, I needed this! 👍🏽

    • @PreMath
      @PreMath  3 роки тому +1

      Thanks Brotha dear for the feedback. You are awesome 👍 Take care dear and stay blessed😃

  • @devondevon4366
    @devondevon4366 3 роки тому +1

    Answer 9.797 of 9.8
    did a similar problem some time ago.
    let A = length of square B= base of the triangle with area 3, and C=length
    of the triangle with the area, 5.
    Ended up with the equation "A^4 - 24A^2 + 48 =0"
    let X = A^2 (A x A or area of square) therefore X^2-24X+48=0
    Solving for X (using the quadratic formula or quadratic calculator) will yield 12 (+ -) 4 sqrt 6. Since theTOTAL area of the three triangles is 12 (3+4+5), then the total area of the triangle inside is 4 sqrt 6 or 9.7979 Answer

    • @PreMath
      @PreMath  3 роки тому +1

      Great feedback my friend. I appreciate that.
      Thank you so much for your continued love and support. Take care dear and stay blessed😃 You are awesome. Keep smiling😊 Enjoy every moment of your life 🌻

  • @shadrana1
    @shadrana1 3 роки тому

    Here is my answer to the same problem around a year ago.
    The notation on the figure was different .
    My square is described as BCEDFA in a clockwise direction from the top LHS of the square.
    Area of triangle EDF=5,Area of triangle FAB=4 and Area of triangle BCE=3.
    Let AF=d and CE= 3d/4 since the areas of triangle BAF=4 and triangle BCE =3 and both had the same height=x.
    Let side of square ABCD =x and area of square is therefore x^2
    Consider triangle BAF,
    4= xd/2
    d=8/x...............(1)
    Consider triangle FDE,
    5=(x-d)(x-3d/4)/2............(2)
    Substitute d=8/x into (2),
    We end up with 10=x^2-14+48/x^2
    Let y=x^2,
    0=y-24+48/y
    Multiply through by y,
    y^2-24y+48=0
    y= 12+4sqrt(6) (-ve sqrt rejected in quadratic formula)
    Area of square ABCD =x^2 = y =12+4sqrt(6),
    Area of triangle BEF= area of ABCD-area of ABF-area of BCE-area of FED
    =(12+4sqrt(6)}4-3-5
    =12+4sqrt(6)-12
    = 4sqrt(6) square units as required.
    Note the -ve value of the sqrt in the quadratic formula was rejected because the area of BEF would have been -ve.

  • @HappyFamilyOnline
    @HappyFamilyOnline 3 роки тому +2

    Amazing video 👍
    Thank you so much sir😀

    • @PreMath
      @PreMath  3 роки тому +1

      Thank you so much for your continued love and support. Take care dear and stay blessed😃 You are awesome. Keep smiling😊 Enjoy every moment of your life 🌻

  • @mathmix1057
    @mathmix1057 3 роки тому

    Thank you for interesting tasks.

  • @אלדד_אלדד
    @אלדד_אלדד 2 роки тому

    why u = 2.2 is not realistic (10:24)?

  • @annatygrys9043
    @annatygrys9043 2 роки тому

    Let's label the side of the square "a" and the bases of the orange and the blue triangels x and y respectively. Than x=6/a and y=8/a.The area of the green triangel =(a-x) (a-y) /2 Hence :(a-6/a)(a-8/a)=10 We receive an biquadratic equation :a^4-24a^2+48 =0.Puting in an auxiliar unknown t=a^2 we get a square equation t^2-24t+48=0. D=384 sqrtD=sqrt16*sqrt 4*sqrt6=4*2*sqrt 6=8 sqrt 6. Therefor we get two walues of t=a^2 :12-4sqrt 6 - to be rejected and 12 +4sqrt 6. Now we have to substract the sum of the given triangels from the calculated area of the whole square :(12 +4sqrt6)-(3+4+5)=12+4sqrt6-12=4sqrt6. Greetings.

  • @beeruawana6662
    @beeruawana6662 3 роки тому +1

    Thank you sir
    Very good question

    • @PreMath
      @PreMath  3 роки тому +1

      So nice of you Beeru! You are awesome 👍 I'm glad you liked it! Please keep sharing premath channel with your family and friends. Take care dear and stay blessed😃

  • @elkhayatila875
    @elkhayatila875 3 роки тому

    Good work teacher , God bless you

    • @elkhayatila875
      @elkhayatila875 3 роки тому

      Why you rejected ( 12-4√6 ) please 🙏

  • @faisal.k01
    @faisal.k01 3 роки тому +1

    Thank you sir, Keep it up👍👍

    • @PreMath
      @PreMath  3 роки тому +2

      Thank you so much Faisal for your continued love and support. Take care dear and stay blessed😃 You are awesome. Enjoy every moment of your life

  • @jamessmith2522
    @jamessmith2522 3 роки тому +1

    It's interesting to note that ABCD does not need to be a square. The result will be the same for any rectangle.

    • @jamessmith2522
      @jamessmith2522 Рік тому

      @Solomon Grundy You are working with areas, and the area of the square/rectangle is only one parameter.

  • @Kris-hz1ns
    @Kris-hz1ns 3 роки тому +3

    Please don't gloss over details which are absolutely important, like 10:27 to 10:33 (time) in your video... (i.e., without giving the reason why you rejected u = 2.2).

    • @maypeaceprevailonearth4191
      @maypeaceprevailonearth4191 3 роки тому

      Ya.... rejecting by saying not realistic is not a logic.

    • @alfreedo3552
      @alfreedo3552 3 роки тому

      If we use that value.. Then area EFC will become - ve... So its not realistic.

    • @umagi3d808
      @umagi3d808 Рік тому

      It's because u=x^2 represents the area of the square, it cannot be smaller than the area of any of the enclosed triangles, the smallest one of which is 3.

  • @thomasaskew1985
    @thomasaskew1985 3 роки тому

    Good one. I almost got it.

  • @lukelhl3522
    @lukelhl3522 2 роки тому

    Thx for your effort :)

  • @rssl5500
    @rssl5500 3 роки тому

    I mean I kinda solve it and I got the equation however I didn’t know how to solve quadratic equations other wise pretty good
    Btw keep up making these videos

  • @Saraa.__.sisiii
    @Saraa.__.sisiii 2 роки тому

    Good techer

  • @shadrana1
    @shadrana1 Рік тому

    I want to prove the Area of triangle FCE is 4sqrt6 square units on the basis that the area of the square is (12+4sqrt6) square units as proved by the lecturer.(x^2= (12+4sqrt6)
    Let FC^2=a^2=((x^4+36)/x^2)=23.44948974 approx =(21+sqrt6) exact value is the same as the decimal value on computer up to 25 places
    Let EC^2=b^2=( (x^4+64)/x^2=24.73401368 approx =(4/3(21-sqrt6)) exact value is the same as the decimal value on computer up to 25 places.
    Let FE^2=c^2=AF^2+AE^2= 21.1850341 approx and the ties up with FE^2= 1/3(63-sqrt6) to 25 decimal places for 25 decimal places.
    The area of triangle CFE =sqrt(4a^2*b^2-(a^2+b^2-c^2)^2)/4 we know x^2=(12+4sqrt6)
    Plug in values of a^2,b^2and c^2 into formula above;
    Area of triangle FCE.
    IFCEI=sqrt( 4*(21+sqrt6)(4/3)(21-sqrt6)-((21+sqrt6)+(4/3)(21-sqrt6)-(1/3)(63-sqrt6))^2/4
    = sqrt(2320-(28)^2/4
    = sqrt(2320-784)/4
    = sqrt(1536)/4
    = sqrt(256*6)/4
    = sqrt(16^2*6)/4
    = (16*sqrt6)/4
    = 4*sqrt6 square units using surd values in the structure.
    Assisted by Wolfram Alpha and hand calculator to work out the exact values in the structure.

  • @stevenreichertart
    @stevenreichertart 3 роки тому +2

    The chance I would’ve figured out these calculations on my own is

    • @paulk5455
      @paulk5455 3 роки тому +1

      My answer exactly!

  • @India-jq7pi
    @India-jq7pi 3 роки тому +1

    Thank you sir

    • @PreMath
      @PreMath  3 роки тому +1

      You are very welcome Gowri!
      Thank you so much for your continued love and support. Take care dear and stay blessed😃 You are awesome. Keep smiling😊

  • @susanalabbe2433
    @susanalabbe2433 3 роки тому

    Thanks a lot

  • @philipkudrna5643
    @philipkudrna5643 3 роки тому

    Very understandable! („Let‘s fill in the blanks...!“)

  • @jumacassimo9885
    @jumacassimo9885 3 роки тому

    saudações meu grande professor respondo pelo nome Juma Cassimo , estudante de Engenharia Moçambique ( Africa) e sou muito fã dos seus trabalhos. Existem vários geômetras mas o Sr e o Melhor em todo universo Eu, gostaria de deixa uma proposta de resolução a cada exercícios ou seja, uma outra forma de resolução.

  • @jaga4059
    @jaga4059 3 роки тому +3

    All ur videos have low sound, pls increase the volume... Thnx

    • @PreMath
      @PreMath  3 роки тому +3

      So nice of you Jagannath! Thanks for your feedback on audio quality. You are awesome 👍 I'm glad you liked it! Please keep sharing premath channel with your family and friends. Take care dear and stay blessed😃

  • @hickskevin
    @hickskevin 3 роки тому

    Why does Heron's formula say A=6?

    • @vikramjeetmann452
      @vikramjeetmann452 3 роки тому

      Actually, 3 ,4 and 5 are areas of triangle and not side length... Hope it's clear now.

  • @reforma715
    @reforma715 Рік тому

    👍👍👍

  • @adgf1x
    @adgf1x 2 роки тому

    Ar=6sq unit.

  • @theophonchana5025
    @theophonchana5025 3 роки тому

    base × height ÷ 2

  • @theophonchana5025
    @theophonchana5025 3 роки тому

    base × height

  • @ScienceNotFaith
    @ScienceNotFaith 3 роки тому

    I like the challenges on your channel, but I really don't like the misrepresented images you give most of the time. In this one, it's obvious the white triangle is not a 345 triangle. Just ask the question with an actual representation.

    • @PreMath
      @PreMath  3 роки тому

      Thanks Kirk for the visit! You are awesome 👍 Take care dear and stay blessed😃 Kind regard

  • @itservice5963
    @itservice5963 3 роки тому

    👌👍👏❤

  • @divyanshuaditya5920
    @divyanshuaditya5920 3 роки тому

    🙏🙏🙏🙏

  • @mathscity949
    @mathscity949 3 роки тому +1

    Too easy, 3 4 5 is a pythagorean triple, the area is 3×4=12

  • @theophonchana5025
    @theophonchana5025 3 роки тому

    bh = b × h

  • @michaelgarrow3239
    @michaelgarrow3239 Рік тому

    Um,,, 3-4-5 is a right angle triangle…
    What?!!
    Never mind… 🙄

  • @aleemam6511
    @aleemam6511 3 роки тому

    🦉