Kablow!

Transformations

Aprenda jogando

Responda a estas perguntas para ganhar energia, depois pesque e explore. Sem precisar de conta.

Para educadores: slides de aula, resumos de revisão prontos para usar de Transformations (Mathematics, Geometry and measures) — use na sua aula ou rode o tópico como atividade interativa de turma que seus aprendizes jogam como um jogo ao vivo.

Notas de aula

Translation

  • A translation slides every point by the same vector \begin{pmatrix} a \\ b \end{pmatrix}: a units right (left if negative) and b units up (down if negative).
  • The shape stays the same size and orientation.

Translation by (3, 1)

Translation by (3, 1)xy-5-4-3-2-112345-5-4-3-2-112345AA′BB′CC′Translation vector (3, 1)

Reflection

  • A reflection flips a shape in a mirror line such as x = 2, y = 0 or y = x. Each point is the same distance from the mirror on the opposite side.
  • Describe it by giving the equation of the mirror line.

Reflection in x = 0

Reflection in x = 0xy-5-4-3-2-112345-5-4-3-2-112345AA′BB′CC′Mirror line: x = 0 (y-axis)

Rotation

  • A rotation turns a shape about a centre. Give centre, angle and direction, except that a 180° rotation does not need direction.
  • A 180° rotation gives the same result in either direction.

A quarter-turn about the origin

A quarter-turn about the originxy-5-4-3-2-112345-5-4-3-2-112345AA′BB′CC′Centre (0, 0) · 90° anticlockwise

Enlargement

  • For enlargement about centre C, image point P′ = C + k(P − C). Distances from C multiply by |k|.
  • A negative k places corresponding image points on the opposite side of C. For k = −½ the image is smaller, while k = −2 makes it larger. For |k| = 1 size is unchanged.

Enlargement with scale factor 2

Enlargement with scale factor 2xy-5-4-3-2-112345-5-4-3-2-112345AA′BB′CC′Centre (0, 0) · scale factor 2

Combining and describing

  • Translation, reflection and rotation give congruent images. Enlargement with nonzero k gives a similar image and is also congruent when |k| = 1.
  • Give the translation vector, reflection line, rotation centre and angle with direction where needed, or enlargement centre and scale factor.

Slides

Sign up free to view the lesson slides

Step through every slide for this topic — plus flashcards and revision notes — with a free account.

Questões de prática

Prévia grátis — 8 de 31 perguntas. Cadastre-se para ver todas.
  1. 1.Which transformation slides a shape without turning it?

    Easy
    • Arotation
    • Breflection
    • Ctranslation
    • Denlargement
  2. 2.What is the image of (2, 3) after translation by \begin{pmatrix} 4 \\ 1 \end{pmatrix}?

    Easy
    • A(6, 4)
    • B(-2, 2)
    • C(8, 3)
    • D(5, 7)
  3. 3.What is the image of (2, 3) after reflection in the x-axis?

    Easy
    • A(2, -3)
    • B(-2, 3)
    • C(-2, -3)
    • D(3, 2)
  4. 4.What is the image of (2, 3) after reflection in the y-axis?

    Easy
    • A(2, -3)
    • B(-2, 3)
    • C(-2, -3)
    • D(3, 2)
  5. 5.What is the image of (2, 3) after reflection in y = x?

    Easy
    • A(3, 2)
    • B(-3, -2)
    • C(2, -3)
    • D(-2, 3)
  6. 6.What is the image of (2, 3) after a rotation of 180° about the origin?

    Easy
    • A(-2, -3)
    • B(2, -3)
    • C(3, 2)
    • D(-3, 2)
  7. 7.What is the image of (2, 0) after a 90° anticlockwise rotation about the origin?

    Easy
    • A(0, 2)
    • B(0, -2)
    • C(-2, 0)
    • D(2, 2)
  8. 8.A shape is enlarged by scale factor 3. A side was 4 cm. What is the new side?

    Easy
    • A7 cm
    • B12 cm
    • C1.33 cm
    • D81 cm

Unlock all 31 questions & more

Crie uma conta grátis para ver todas as perguntas, os slides, flashcards e resumos de revisão deste tópico.

Provas anteriores

A prática com provas anteriores deste tópico chega em breve.
Em breve