Mathematics for IGCSE & O level - Equations (Section 2)

  • 1
    In factorization, what is the next step when you have an equation like x² - 9 = 0?
    Antwort
    (B)
    Factor by the method 'difference of two squares'.
  • 2
    In the formula for the area of a circle, A = πr², what does 'r' represent?
    Antwort
    (B)
    Radius
  • 3
    What value of x makes the following true: 2x + 1 = x - 3?
    Antwort
    (B)
    -4
  • 4
    What type of expression can be solved by completing the square?
    Antwort
    (C)
    Quadratic equations.
  • 5
    Given the equation C = d + KR. Solve for R.
    Antwort
    (A)
    R = (C - d)/K
  • 6
    What should you do when a quadratic equation has a negative 'c' value when attempting to factorize?
    Antwort
    (B)
    Find two numbers with different signs.
  • 7
    In the expression x² - 6x + 9, what is the result of factoring?
    Antwort
    (B)
    (x-3)(x-3)
  • 8
    In the equation y = mx + c, what does 'm' represent?
    Antwort
    (B)
    The slope
  • 9
    What's the significance of the sign of the 'b' term (coefficient of the x term) in the quadratic equation?
    Antwort
    (B)
    It affects the x-coordinate of the vertex.
  • 10
    What is the main goal when using substitution to solve simultaneous equations?
    Antwort
    (C)
    To eliminate one of the variables.
  • 11
    What's the first step when solving an equation using the quadratic formula?
    Antwort
    (A)
    Identify the values of a, b, and c.
  • 12
    Solve: 1/3x - 1 = 5
    Antwort
    (C)
    18
  • 13
    How is the value of the subject variable changed in the equation by doing addition or subtraction?
    Antwort
    (B)
    The value of the subject variable may change.
  • 14
    How many possible solutions are there for a quadratic equation?
    Antwort
    (B)
    Two
  • 15
    If 2x - 7 = 9, what is the value of x?
    Antwort
    (C)
    16
  • 16
    Identify the errors that commonly occur when solving equations with fractions:
    Antwort
    A
    B
    C
  • 17
    When factorizing, what sign should the factors of 'c' have if 'c' is positive and 'b' is negative?
    Antwort
    (B)
    Both negative.
  • 18
    What happens to the roots of the equation if the discriminant is negative?
    Antwort
    (C)
    There are no real roots.
  • 19
    In the context of solving simultaneous equations, what does the term 'elimination' refer to?
    Antwort
    (A)
    Adding or subtracting the equations to remove a variable
  • 20
    Which are the common steps in the factorization method?
    Antwort
    A
    C
    D
  • 21
    Which of the following methods are suitable for solving the equation: x² - 4 = 0?
    Antwort
    (D)
    All of the above.
  • 22
    Which of the following is a suitable example for using factorization?
    Antwort
    (A)
    x² + 2x + 1 = 0
  • 23
    If the sides of a triangle are a, b, and c. If a = 3, b = 4, and c = 5, what kind of triangle is it?
    Antwort
    (C)
    Right
  • 24
    If 4x + 8 = 20, what is the value of x?
    Antwort
    (A)
    3
  • 25
    Solve for x: 4(x - 2) = 16
    Antwort
    (A)
    2
  • 26
    What does 'c' represent in the standard quadratic equation ax² + bx + c = 0?
    Antwort
    (C)
    The constant term
  • 27
    Which technique is appropriate for solving equations of the form (x - a)(x + b) = 0?
    Antwort
    (C)
    Setting each factor equal to zero
  • 28
    What is the slope-intercept form of a linear equation?
    Antwort
    (B)
    y = mx + b
  • 29
    What is the solution to the equation: x/5 - 2 = 3?
    Antwort
    (B)
    25
  • 30
    What is the most reliable method for solving quadratic equations, especially when factorization is difficult or impossible?
    Antwort
    (C)
    The quadratic formula.
  • 31
    What is the method for solving the equation: (x-2)(x+3) = 0?
    Antwort
    (C)
    Setting each factor to zero.
  • 32
    If the length of a rectangle is 12 and the perimeter is 36, what is the width?
    Antwort
    (A)
    6
  • 33
    What step immediately follows isolating the variable when solving for the subject of a formula?
    Antwort
    (C)
    Using inverse operations to eliminate terms on the same side as the variable.
  • 34
    If the perimeter of a square is 20, what is the length of one side?
    Antwort
    (B)
    5
  • 35
    How should you handle the case when a quadratic equation's discriminant is zero?
    Antwort
    (D)
    Only one real solution, a repeated root.
  • 36
    Solve the equation: 2x - 4 = x + 1
    Antwort
    (A)
    5
  • 37
    What is the next step in solving 5x - 4 = 11?
    Antwort
    (B)
    Add 4 to both sides
  • 38
    What is the area of a rectangle if the length is 10 cm and the width is 5 cm?
    Antwort
    (B)
    50 sq cm
  • 39
    When solving for a variable, what operations are considered 'inverse' operations?
    Antwort
    (B)
    Subtraction and division
  • 40
    When solving a quadratic equation by factorization, what should you do if 'c' is negative and you have an equation like x² + bx + c = 0?
    Antwort
    (B)
    Find two numbers with different signs that multiply to give 'c' and add to give 'b'.
  • 41
    When solving for x in the equation 5x = 20, what is the correct step?
    Antwort
    (B)
    Divide both sides by 5
  • 42
    What is the main goal of solving simultaneous equations?
    Antwort
    (C)
    To find values for both variables that satisfy both equations.
  • 43
    Solve for x: x/2 + 5 = 9
    Antwort
    (C)
    8
  • 44
    What is the value of x in the equation 2x + 5 = 11?
    Antwort
    (A)
    3
  • 45
    What would be the result of the equation x² = 9 by using the method of "difference of two squares"?
    Antwort
    (C)
    x = 3 or -3
  • 46
    If a is 7 and b is 4, what is the value of (a+b) * a ?
    Antwort
    (A)
    77
  • 47
    What is the simplified form of the expression: 3(x + 2) - x?
    Antwort
    (A)
    2x + 6
  • 48
    What is the y-intercept of the linear equation y= -2x + 5?
    Antwort
    (B)
    5
  • 49
    What is the primary goal when solving a system of simultaneous equations?
    Antwort
    (B)
    To find the points of intersection.
  • 50
    If 3x - 5 = 4, what is x?
    Antwort
    (B)
    1