Can you find the distance X between two semicircles? | Radii of semicircles are 21 and 6

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  • Опубликовано: 25 окт 2024

Комментарии • 67

  • @walcholjacob4259
    @walcholjacob4259 Год назад +6

    Absolutely wonderful ❤

    • @PreMath
      @PreMath  Год назад +1

      Glad you think so!
      Thanks for your feedback! Cheers!
      You are awesome. Keep smiling👍
      Love and prayers from the USA! 😀

  • @spiderjump
    @spiderjump Год назад +34

    OP^2= 36^2 + 15^2
    OP = 39
    x=39-21-6=12

    • @PreMath
      @PreMath  Год назад +1

      Thanks for sharing! Cheers!
      You are awesome. Keep it up 👍
      Love and prayers from the USA! 😀

    • @kokodin5895
      @kokodin5895 Год назад +4

      yes i did that exactly the same way before watching tthe explanation that is surprisingly more complicated :]

    • @batavuskoga
      @batavuskoga Год назад +2

      I also solved it the same way before watching the video.

    • @carstenlarsen8144
      @carstenlarsen8144 Год назад +2

      @@kokodin5895 yes...he really likes to be professor- aknowledged i mean..
      take an easy problem and make it hard.

    • @vladanterzic
      @vladanterzic Год назад +1

      Right, clean and simple. I dont unnderstand why the complicating

  • @wackojacko3962
    @wackojacko3962 Год назад +3

    SNL Church Lady says, "isn't that special!" ....I say of course it is, and the Circle Theorem applied to this problem using radius and tangent angle 90⁰ is a very special case of the 7 main Circle Theorems. I absolutely love it. 🙂

  • @emadalkindy2154
    @emadalkindy2154 Год назад +2

    U can use Pythagoras for the triangle of 36 and 15 sides to have 39 units for the 3rd side and consequently x=39-(6+21)=12

  • @TurquoizeGoldscraper
    @TurquoizeGoldscraper Год назад +10

    I did the same as you, but didn't use OP = x + 27 for the Pythagorean theorem which then requires the quadratic formula; I used OP as a whole to get 39, and then subtracted 21 and 6 to get 12.

    • @solomou146
      @solomou146 Год назад

      Πολύ σωστά. Ακριβώς έτσι και αποφεύγουμε την εξίσωση 2ου βαθμού.

  • @SuperBiman
    @SuperBiman Год назад +10

    In the RT angle triangle OEP, OE= 15, EP=36.
    Using Pythagorean theorem
    OE^2+EP^2=OP^2
    225+1296=OP^2
    OP=√1521= 39
    Hence X = 39-21-6= 12

    • @awandrew11
      @awandrew11 Год назад +1

      Absolutely and it won't give you a X square to dwell on!

    • @bryanwilson8130
      @bryanwilson8130 Год назад +1

      Nothing like squaring things just to then have to root them later... the 6 and 21 will still be 6 and 21

  • @paullangenkamp
    @paullangenkamp Год назад +17

    There is a 5, 12, 13 Pythagorean triple hidden in there. 😊

    • @MrPaulc222
      @MrPaulc222 24 дня назад

      Good spot. I saw the 15, 36, 39 but didn't connect with 5, 12, 13 even though they are all integers.

  • @arthurschwieger82
    @arthurschwieger82 Год назад +1

    My brain did this in more steps. I took the OP distance for my C in the Pythagorean Theorem. 15^2 + 36^2 = C^2. This comes to C = Sqrt(1,521) = 39. Then the basic math of 39 - 21 - 6 = 12. Just another way to solve the same problem. Love these!

  • @bertblankenstein3738
    @bertblankenstein3738 Год назад +1

    I like how you broke down the geometric problem, but it would be SO MUCH SIMPLER to solve for OP and then subtract the two radii. The expasion of (x+27)**2 seems needlessly complicated. Thank you for the video.

  • @AnonimityAssured
    @AnonimityAssured Год назад +1

    Is that a scaled 5-12-13 triangle I see? I do like a whole number answer.

  • @vaibhavgupta5359
    @vaibhavgupta5359 Год назад +2

    Sir outstanding video❤

    • @PreMath
      @PreMath  Год назад

      Glad you think so!
      Thanks for your continued love and support!
      You are awesome. Keep smiling👍
      Love and prayers from the USA! 😀

  • @montynorth3009
    @montynorth3009 Год назад +2

    Triangle OPE is of the 5,12,13 type.😊

  • @DB-lg5sq
    @DB-lg5sq Год назад +1

    شكرا لكم
    يمكن استعمال X نقطة تقاطع (AB) و (OP) والمثلث القاءم الزاوية AOX.....

  • @KAvi_YA666
    @KAvi_YA666 Год назад

    Thanks for video.Good luck sir!!!!!!!!!!!!!

  • @albertofernandez6861
    @albertofernandez6861 Год назад

    Using Pytagorean theorem over the APB triangle:
    y=AP
    So, y²=15²+36²
    y²=225+1296
    y²=1521
    y=√1521
    y=39
    y=21+6+x
    39=21+6+x
    x=12

  • @theoyanto
    @theoyanto Год назад

    Coffee time problem, but only because I recognised that you used this approach in a similar question ...
    Glad I was paying attention 🤓👍🏻

  • @naficokal2013
    @naficokal2013 Год назад +1

    there is a shorter calculation... 15^2+36^2=op^ therefore op=39, then x=39 - (21+6) which is 12... anyway nice one thx

  • @williamwingo4740
    @williamwingo4740 Год назад

    With you as far as constructing triangle OEP. Then I realized that OEP is an integer Pythagorean triple, 15-36-39; So OP = 39 and x = 39 -- 27) = 12. Elapsed time about 90 seconds.
    Cheers. 🤠

  • @EnnioPiovesan
    @EnnioPiovesan Год назад +1

    If PB is extended beyond B and the parallel to OP is drawn through A until it meets the extension of PB in R, the parallelogram OPRA is obtained. PR=AO=21 so BR=21-6=15. In the right triangle ABR we have BR=3*5, AB=3*12 so AR closes the Pythagorean triple (5,12,13) ​​with 3*13. OP = AR --> 21+x+6=3*13 --> 3*7+x+3*2=3*13 --> x= 3(13-7-2)=3*4=12.

    • @waheisel
      @waheisel Год назад

      Good point. When you see the 5-12-13 right triangle you can figure out the solution in your head.

  • @ybodoN
    @ybodoN Год назад

    Generalized: _x = √((R − r)² + a²) − R − r_ where _R_ is the radius of the large circle, _r_ is the radius of the small circle and _a_ is the tangent AB.

  • @quigonkenny
    @quigonkenny 8 месяцев назад

    As OC and PD are radii of their semicircles, they equal 21 and 6 respectively, and OP = 21+x+6.
    Let E be the point on OA where PE is perpendicular to OA. As AB is tangent to both semicircles, PE is parallel to AB, and EPBA is a rectangle.
    Triangle ∆PEO:
    a² + b² = c²
    (21-6)² + 36² = (x+27)²
    x² + 54x + 729 = 225 + 1296 = 1521
    x² + 54x - 792 = 0
    x² + 66x - 12x - 792 = 0
    x(x+66) - 12(x+66) = 0
    (x-12)(x+66) = 0
    x - 12 = 0 | x + 66 = 0
    x = 12 ✓ | x = -66 ❌ x > 0
    x = 12

  • @limfilms1089
    @limfilms1089 Год назад

    I drew BE as a parallel to OP. E is on AO. Then used Pythagorean theorem to find BE=39 which is equal to OP thus 39-21-6=12.

  • @dreael
    @dreael Год назад

    In this example, there is no need to use the cumbersome way of quadratic equation: On the 15^2+36^2=(x+27)^2 just leave the term on the right side as is: 225+1296=(x+27)^2 => 1521=(x+27)^2 Take the square root now: sqrt(1521)=sqrt((x+27)^2). Since OP is a positive value, we only need to take care about the positive value: 39=x+27 => 39-27=x -> x=12. Alternatively, we also can use 15^2+36^2=OP^2 and 21+x+6=OP So it will be obvious to solve the first equation for OP first which will result in OP=39. Then just replace OP on the second equation: 21+x+6=39 which is trivial to solve.

  • @dakshgiriraj4468
    @dakshgiriraj4468 Год назад +1

    nice one yr..superb

    • @PreMath
      @PreMath  Год назад

      Thanks for your continued love and support!
      You are awesome. Keep smiling👍
      Love and prayers from the USA! 😀

  • @vidyadharjoshi5714
    @vidyadharjoshi5714 Год назад

    Extend BP by 15 to R and join RO ( this is 36). OPsq = 36sq + 15sq = 1521. OP = 39. So X = 39 - (21 + 6) = 12.

  • @MrPaulc222
    @MrPaulc222 25 дней назад

    36^2 + 15^2 = 1296 + 225 = 1521, so OP also equals sqrt(1521) = 39.
    39 - 21 - 6 = 12.
    x = 12.

  • @MarieAnne.
    @MarieAnne. Год назад

    a = 15 = 3 * 5
    b = 36 = 3 * 12
    Therefore, we have a 5:12:13 right triangle and
    c = OP = 3 * 13 = 39
    x + 27 = 39
    x = 12

  • @jaii5955
    @jaii5955 Год назад

    I solved it. Thanks for such questions 😊

  • @Copernicusfreud
    @Copernicusfreud Год назад

    Yay! I solved it.

  • @jaii5955
    @jaii5955 Год назад

    Please start some questions about cubic equation , please it is my request :(

  • @jmlfa
    @jmlfa Год назад

    Draw OX parallel to AB. XB = 21, therefore(sic) XP=21 and XP=15.... [X+27] = sqrt[1521]

  • @DougYerger
    @DougYerger Год назад

    The -66 answer is correct as well. It places the smaller semicircle on the lefthand side of the larger semicircle with a gap of 12 between them.

    • @fernandoprieto9171
      @fernandoprieto9171 Год назад

      Correcto; físicamente la ecuación nos entrega dos respuestas valederas.

  • @madhusudangupta3661
    @madhusudangupta3661 Год назад

    ∆ OPE; PE = 36, OE = 15 so OP= 39, X= 39-21-6=12

  • @kokodin5895
    @kokodin5895 Год назад

    that was an easy one

  • @carstenlarsen8144
    @carstenlarsen8144 Год назад

    let the distance be 21+6+x = root 2 of (36^2+15^2).....
    root 2 of (1296+225)= root 2 og 1521 = 39....easy bc 40^2 = 1600 and 1 step back is 1600 -40-39 = 1521...
    now 39-21-6 = 12
    all fast and in head.. as long as you know your square numbers

  • @Su4ji
    @Su4ji Год назад

    Tripel pithagoras 5,12,13
    X = 39 - 27 = 12

  • @harikatragadda
    @harikatragadda Год назад +1

    Nice!
    Some steps could have been dropped.
    1521 = 39² = (x+25)²
    x = ±39 - 25
    x = 12

    • @PreMath
      @PreMath  Год назад

      Thanks for sharing! Cheers!
      You are awesome. Keep it up 👍
      Love and prayers from the USA! 😀

  • @misterenter-iz7rz
    @misterenter-iz7rz Год назад +1

    Using tecnique of similar triangle, x=(36-21x12/13-6x12/13)x13/12=(36-27x12/13)x13/12=39-27=12.🙂

    • @PreMath
      @PreMath  Год назад +1

      Thanks for sharing! Cheers!
      You are awesome. Keep it up 👍
      Love and prayers from the USA! 😀

    • @ashieshsharmah1326
      @ashieshsharmah1326 Год назад

      Can you please explain little bit .

    • @misterenter-iz7rz
      @misterenter-iz7rz Год назад

      @@ashieshsharmah1326 Draw radii of two circles to get a trapezium, and a line parallel to the external tangent joining the center of the small semicircle, we get one rectangle dimension 36x6 and a right angled triangle 15x36x39(in ratio 5:12:13),and draw two lines from the two end points of perpendicular to the external tangent,.......

  • @hamidaqayyum1266
    @hamidaqayyum1266 Год назад

    []《 *_Absolutely Beautiful Presentation and sharing_* 》 []
    []《 *_Greetings and Blessings from Hamida Qayyum_* 》 [] LIKE 240

  • @88Truth380
    @88Truth380 Год назад

    Another way:
    Extend the line BP down with 21 length. Connect the point to O to form a rectangular. Then, you will form a right angle triangle below with the same of yours.
    The rest of calculations is the same as yours 😊

  • @jahazielmeza1758
    @jahazielmeza1758 Год назад

    Lo hizo demasiado largo.
    Se puede hacer en dos pasos.
    1-calcular OP con el teorema de pitágoras.
    2-Al resultado anterior restarle 21 y 6.
    Eso es todo

  • @alster724
    @alster724 Год назад

    The Pythagorean Theorem did pay off

  • @AmirgabYT2185
    @AmirgabYT2185 8 месяцев назад +1

    12

  • @misterenter-iz7rz
    @misterenter-iz7rz Год назад +1

    Second one to addlike.😚

    • @PreMath
      @PreMath  Год назад

      Thank you! Cheers!
      You are awesome. Keep it up 👍
      Love and prayers from the USA! 😀

  • @alexniklas8777
    @alexniklas8777 Год назад

    x= 66😮😮😮
    x= (36^2+15^2)^(1/2)- 21- 6= 12😊

  • @缘投囝仔
    @缘投囝仔 Год назад

    Pythagoras theorem

  • @mohamadtaufik5770
    @mohamadtaufik5770 Год назад

    Easy, x=12

  • @mega_mango
    @mega_mango Год назад

    12 ezzz