Skip to content
LessonPrint

Triangles by Sides is a free printable Grade 5 maths worksheet on classifying triangles, aligned to Common Core standard 5.G.B.3. It prints 5 questions with an answer key on its own sheet of paper, in 25 versions that each ask different questions, so no two pupils in the class work from the same page. Print it from the browser or download it as a PDF — no account, no email.

Set 19 of 25 · the same problems every time you open this link.

Next set

One paper per pupil

12345678910111213141516171819202122232425

Set 1 has all 25 in a single PDF. All 25 sets ask different questions.

Triangles by Sides

5.G.B.3

NameDate

Sort each one into the right box.

1.Sort each one into the right box.

Sort: two equal angles, sides 4, 6, 9, all angles 60°, sides 3, 5, 7

EquilateralIsoscelesScalene
2.Sort each one into the right box.

Sort: two equal angles, sides 6, 6, 6, no equal sides, sides 4, 4, 6

EquilateralIsoscelesScalene
3.Sort each one into the right box.

Sort: sides 3, 5, 7, sides 4, 4, 6, all angles 60°, sides 4, 6, 9

EquilateralIsoscelesScalene
4.Sort each one into the right box.

Sort: sides 5, 5, 8, two equal angles, sides 6, 6, 6, all sides 5 cm

EquilateralIsoscelesScalene
5.Sort each one into the right box.

Sort: sides 6, 6, 6, sides 4, 4, 6, all sides 5 cm, sides 5, 5, 8

EquilateralIsoscelesScalene

LessonPrint · 5.G.B.3 · Set 19 · free to copy for classroom use

Answer key — Triangles by Sides

Set 19. Prints on its own sheet.

  1. 1.Equilateral: all angles 60°; Isosceles: two equal angles; Scalene: sides 4, 6, 9, sides 3, 5, 7
  2. 2.Equilateral: sides 6, 6, 6; Isosceles: two equal angles, sides 4, 4, 6; Scalene: no equal sides
  3. 3.Equilateral: all angles 60°; Isosceles: sides 4, 4, 6; Scalene: sides 3, 5, 7, sides 4, 6, 9
  4. 4.Equilateral: sides 6, 6, 6, all sides 5 cm; Isosceles: sides 5, 5, 8, two equal angles; Scalene: —
  5. 5.Equilateral: sides 6, 6, 6, all sides 5 cm; Isosceles: sides 4, 4, 6, sides 5, 5, 8; Scalene: —

Last reviewed 2026-09-05. Aligned to 5.G.B.3 of the Common Core State Standards for mathematics.