CrazyEngineers
  • Ankita
    Ankita

    MemberNov 2, 2011

    Grand Quiz Question #2

    The 2nd Question of the #-Link-Snipped-# is as follows -

    Q. Using basic geometry rules, find the value of 'x' in the following figure.
    [Question is worth 15 CE-Coins]

    You shall not use trigonometry rules such as sines and cosines.

    find-x

    HINT: The image has not been drawn to proportion. It is advised that you draw the diagram yourself before solving.

    A few instructions -


    1. Your answer should be the
    value of x along with the approach you used to solve this problem.
    We expect you to give a logical explanation of how you reached to the solution.

    2. Answers with no explanation at all will be disqualified.

    3. Just as we said before, the fastest to answer correctly wins!

    Replies
Howdy guest!
Dear guest, you must be logged-in to participate on CrazyEngineers. We would love to have you as a member of our community. Consider creating an account or login.
Replies
  • Anoop Mathew

    MemberNov 2, 2011

    x is 20 degrees. Exterior Angle is equal to interior opposite angle. angle ART is 20, so x also becomes 20
    Are you sure? This action cannot be undone.
    Cancel
  • Anoop Mathew

    MemberNov 2, 2011

    I meant angle SRT is 20, not ART...Typing mistake.
    Are you sure? This action cannot be undone.
    Cancel
  • PraveenKumar Purushothaman

    MemberNov 2, 2011

    The answer is 20 degrees. I drew it using hand and measured it. I can also be done as this way.
    R = 100 = 80 + 80 + R.
    P = 10.
    Mid Pt = 180 - 60 - 70 = 130.
    So, 150 - 130 = 20!
    Are you sure? This action cannot be undone.
    Cancel
  • Kaustubh Katdare

    AdministratorNov 2, 2011

    Do NOT make assumptions, folks 😀
    Are you sure? This action cannot be undone.
    Cancel
  • Sagar07

    MemberNov 2, 2011

    In triangle PQR, angle R=180-angle P- angle Q= 180- 80-80= 20....
    angle RTS is 90..
    hence in triangle RTS, angle RST=180- angle R- angle RTS=189-20-90=70
    angle PSQ=180-10-90=80

    hence angle TSQ=180- angle PSQ- angle RST=180-70-80=30

    in triangle TSO, x= 180-90-angle TSQ= 180-90-30=60

    assuming intersection point is o......
    Are you sure? This action cannot be undone.
    Cancel
  • Sahithi Pallavi

    MemberNov 2, 2011

    i can give you the explanation in this figure,
    so by considering the middle triangle,
    20+ (50-x)+ (150-x) = 180.
    220-2x = 180.
    40 =2x.
    x=20!
    Are you sure? This action cannot be undone.
    Cancel
  • Sahithi Pallavi

    MemberNov 2, 2011

    sorry, forgot to add this image X
    Are you sure? This action cannot be undone.
    Cancel
  • bhavna gupta

    MemberNov 2, 2011

    Let the point inside the triangle be taken as A
    In triangle PQR
    According to the property 1:all the sum of all the angles of a triangle is 180 or 360
    therefore, P+Q+R=180
    80+80+R=180
    R=20

    In triangle RSQ
    as above property.......R+Q+S=180
    20+20+S=180
    S=140

    Now,acc to the property 2:sum of all the angles made across the line is 180
    therefore,In triangle POS...
    S=180-140
    S=40

    Again In triangle POS..
    P+S+O=180
    10+40+O=180
    O=130
    now In triangle POQ
    P+Q+O=180
    70+60+O=180
    O=50

    In triangle RST
    R+S+T=180
    20+140+T=180
    T=20

    now acc to property 2:
    O in triangle SOT
    130+O=180
    O=50

    acc to property 2:
    O in triangle QOT
    O=130

    In triangle QOT
    t=30
    now acc to property 2: At T
    T of triangle RST+T of triangle SOT+T of triangle QOT=180
    20+T+30=180
    Therefore Final answer is....T=130.......
    Are you sure? This action cannot be undone.
    Cancel
  • Sudha Warad

    MemberNov 2, 2011

    By Z property angle T=70, Given PTQ angle =90, and RTQ=180 so x=180-70-90=20.......
    thats all.........
    Are you sure? This action cannot be undone.
    Cancel
  • Kaustubh Katdare

    AdministratorNov 2, 2011

    Repeat: DO NOT make assumptions, please! :😀
    Are you sure? This action cannot be undone.
    Cancel
  • CIVILPRINCESS

    MemberNov 2, 2011

    X is 60

    the triangles RST AND QST are similar... since QS=SR (OPPOSITE ANGLES ARE 20) and they have a common side ST. (SSA congruency)

    i.e. RTS = STQ. => 90

    X+30 = 90. => X=60.
    Are you sure? This action cannot be undone.
    Cancel
  • CIVILPRINCESS

    MemberNov 2, 2011

    untitled

    THE SIDEs I'VE marked (SQ and SR) are equal and one common side ST and one equal angle 20. so SAS congruency...
    Are you sure? This action cannot be undone.
    Cancel
  • ultimate_k

    MemberNov 2, 2011

    x is equal to 50 degree (trial and error method).
    Are you sure? This action cannot be undone.
    Cancel
  • Guneet Khanuja

    MemberNov 2, 2011

    x= 70 degree.
    method: let angle TSQ= y, and angle RST= z.
    therefore,
    y+z=140
    x+y=130
    z-x=10.
    and SR= SQ
    Are you sure? This action cannot be undone.
    Cancel
  • eternalthinker

    MemberNov 2, 2011

    Can't find a logical way to x!

    Appreciate the question anyways 😀
    Are you sure? This action cannot be undone.
    Cancel
  • eternalthinker

    MemberNov 2, 2011

    The thumbnail was from previous attempts to answer. Auto-saved!
    Are you sure? This action cannot be undone.
    Cancel
  • lovejeet

    MemberNov 2, 2011

    x=30...
    psq=180-spq-sqp=40------------A
    angle sot(o is the intersection of sq and tp)=50---------------B
    prq=20-----------------------C
    in triangle pts, pst=140-------------D
    THerefore, tsq=100...
    Therefore, x=180-100-50=30
    HENCE, X=30.
    Are you sure? This action cannot be undone.
    Cancel
  • abhinaykumar

    MemberNov 2, 2011

    by simple triangle method all angles in triangle= 180 using this equation we can solve the problem
    as we all can see there are two rightangled triangles
    using those we can say the angle of x is 20
    Are you sure? This action cannot be undone.
    Cancel
  • sunil pal

    MemberNov 2, 2011

    triangle STR&STQ
    ST=ST
    angle SQT=angle SRT
    in triangle SQR SR=SQ
    so angle RST=angle TSQ
    angle RSQ=140=angle RST+angle TSQ
    so angle RST = angle TSQ=70
    in triangle SPQ
    angle PSQ=40
    and angle PTQ=30
    and
    X+angle PTQ=90
    so
    X=60 ANS
    X=
    Are you sure? This action cannot be undone.
    Cancel
  • Ankita Katdare

    AdministratorNov 2, 2011

    Entries for this question are now closed.

    Check out today's question between 6pm to 9pm IST.
    Are you sure? This action cannot be undone.
    Cancel
Home Channels Search Login Register