logo

CuriousTab

CuriousTab

Discussion


Home Aptitude Elementary Algebra Comments

  • Question
  • If a2 + b2 + c2 = 2 (a – b – c) – 3 then the value of 2a – 3b + 4c is


  • Options
  • A. 3
  • B. 1
  • C. 2
  • D. 4

  • Correct Answer


  • Explanation

    As per the given question , we have
    a2 + b2 + c2 = 2 (a – b –c) –3
    ⇒ a2 + b2 + c2 = 2a + 2b + 2c + 3 = 0
    ⇒ a2 – 2a + 1 + b2 + 2b + 1 + c2 + 2c + 1 = 0
    ⇒ (a –1)2 + (b + 1)2 + (c + 1)2 = 0
    [If x2 + y2 + z2 = 0 ⇒ x = 0; y = 0; z = 0]
    ∴ a – 1 = 0 ⇒ a = 1
    b + 1 = 0 ⇒ b = – 1
    c + 1 = 0 ⇒ c = – 1
    ∴ 2a – 3b + 4c = 2 + 3 – 4 = 1


  • Elementary Algebra problems


    Search Results


    • 1. If 4x = 18y, then the value of ( x/y - 1) is

    • Options
    • A. 1 3
    • B. 7 2
    • C. 2 3
    • D. 3 2
    • Discuss
    • 2. 
      If x = 1 + ?2 + ?3, then the value of ( 2x4 ? 8x3 ? 5x2 + 26x ? 28) is

    • Options
    • A. 6 ?6
    • B. 0
    • C. 3 ?6
    • D. 2 ?6
    • Discuss
    • 3. 
      Area of the trapezium formed by x-axis; y-axis and the lines 3x + 4y = 12 and 6x + 8y = 60 is:

    • Options
    • A. 37.5 sq. unit
    • B. 31.5 sq. unit
    • C. 48 sq. unit
    • D. 36.5 sq. unit
    • Discuss
    • 4. 
      If a =
      ? 3 - ? 2
      , b =
      ? 3 + ? 2
      , then the value of
      ?3 + ?2 ?3 - ?2
      a 2
      +
      b 2
      is :
      b a

    • Options
    • A. 900
    • B. 970
    • C. 1030
    • D. 930
    • Discuss
    • 5. 
      In the xy?coordinate system, if ( a, b) and ( a + 3, b + k) are two points on the line defined by the equation x = 3y ? 7, then k =?

    • Options
    • A. 7 3
    • B. 1
    • C. 9
    • D. 3
    • Discuss
    • 6. 
      If x = 2 + ?3, y = 2 - ?3, then the value of
      x 2 + y 2
      is
      x3 + y3

    • Options
    • A. 7 38
    • B. 7 40
    • C. 7 19
    • D. 7 26
    • Discuss
    • 7. 
      If 2x -
      1
      = 6, then the value of x2 +
      1
      is
      2x 16x2

    • Options
    • A. 19 2
    • B. 17 2
    • C. 18 2
    • D. 15 2
    • Discuss
    • 8. 
      If x =
      4ab
      , then the value of
      x + 2a
      +
      x + 2b
      is
      a + b x - 2a
      x - 2b

    • Options
    • A. a
    • B. b
    • C. 0
    • D. 2
    • Discuss
    • 9. 
      The area of the triangle formed by the lines 5x + 7y = 35, 4x + 3y = 12 and x-axis is

    • Options
    • A. 160 sq.unit 13
    • B. 150 sq.unit 13
    • C. 140 sq.unit 13
    • D. 10 sq.unit
    • Discuss
    • 10. 
      The area (in sq. unit) of the triangle formed by the three graphs of the equations x = 4, y = 3, and 3x + 4y = 12, is

    • Options
    • A. 12
    • B. 10
    • C. 6
    • D. 8
    • Discuss


    Comments

    There are no comments.

Enter a new Comment