Common Core: 8th Grade Math

Explore the foundational concepts of mathematics, including algebra, geometry, and data analysis, essential for 8th-grade students.

Advanced Topics

Transformations and Congruence

Moving and Matching Shapes

Transformation means changing a shape's position, size, or orientation. In 8th grade, you'll learn about translations (slides), rotations (turns), reflections (flips), and dilations (resizing).

Types of Transformations

  • Translation: Slide the shape up, down, or sideways.
  • Rotation: Turn the shape around a point.
  • Reflection: Flip the shape over a line.
  • Dilation: Make the shape bigger or smaller but keep its proportions.

If two shapes match exactly after a transformation (except for dilations), they are congruent.

Why It Matters

Understanding transformations helps in art, design, and even robotics, where you need to predict how objects move and fit together.

Examples

  • A triangle flipped over the x-axis is a reflection.

  • A logo resized to fit a t-shirt uses dilation.

In a Nutshell

Transformations show how shapes move or change, and congruence shows when shapes are exactly alike.

Key Terms

Transformation
A change in a shape's position, size, or orientation.
Congruent
Shapes that are exactly the same size and shape.