Translations

A translation is a transformation that slides every point of a figure the same distance in the same direction. Nothing rotates and nothing flips — the figure simply glides to a new position. A translation is a , so the image stays congruent to the original.

Translating by a vector

The slide is described by a translation vector a,b\langle a, b \rangle, where aa is the horizontal shift and bb is the vertical shift.

Make a prediction: The point (2, 3) is translated by the vector ⟨5, −1⟩ — 5 units right and 1 unit down. Where does its image land?

Applying the vector to a point adds its components coordinate-wise:

(x,y)(x+a,y+b)(x, y) \mapsto (x + a,\, y + b)

For example, translating the point (1,1)(1, 1) by 3,2\langle 3, -2 \rangle moves it to (4,1)(4, -1). Because the same vector is applied to every vertex, the shape keeps its size, its orientation, and the order of its vertices — only its location changes.

Drag the shift sliders and watch triangle ABC slide to A′B′C′.

3
-2
A triangle ABC translated by the vector (3, -2) → triangle A′B′C′.

Practice

Score: 0/2

  1. 1.Translate the point (2, 5) by the vector ⟨4, -3⟩. Where does it land?
  2. 2.A vertex sits at (−1, 4). After translating by ⟨6, 2⟩, what is its new y-coordinate?
For teachers

Standard, common misconceptions, and suggested use will live here.