Sorting Shapes by Lines and Angles
Aligned to 4.G.A.2 — Common Core State Standards for Mathematics.
What this lesson teaches
You can classify shapes by their lines and angles. Parallel lines never cross and stay the same distance apart. Perpendicular lines cross to make a right angle (a square corner). A right triangle has one right angle.
Worked example
Look at a rectangle. Its opposite sides are parallel, and every corner is a right angle where sides are perpendicular. A triangle with one square corner is a right triangle; a triangle with all sharp corners is not.
Practice questions
- Name one shape that has two pairs of parallel sides.
- Draw a triangle that has a right angle and label the right angle.
- True or false: perpendicular lines always form a right angle. Explain.
Watch the lesson
Every lesson comes with a video taught in English and Spanish — the same video the QR code in the printed workbook opens.
▶ Watch this lessonEn español
Clasificar figuras por lineas y angulos
Puedes clasificar figuras por sus lineas y angulos. Las lineas paralelas nunca se cruzan y siempre estan a la misma distancia. Las lineas perpendiculares se cruzan formando un angulo recto (una esquina cuadrada). Un triangulo rectangulo tiene un angulo recto.
Ejemplo: Observa un rectangulo. Sus lados opuestos son paralelos y cada esquina es un angulo recto donde los lados son perpendiculares. Un triangulo con una esquina cuadrada es un triangulo rectangulo; uno con todas las esquinas agudas no lo es.
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