Arithmagon puzzles

Triangles where each side is the product of two circles. Find the circle numbers.

About this worksheet

Each arithmagon is a triangle with a number on every side. The side number is the product of the two circles at its ends, and students work backwards to find the circles.

It is a gentle introduction to factoring and to the algebra idea of solving for unknowns. Turn on the hint to give one circle for younger students.

Printing

US Letter or A4, portrait: choose your paper size above. Print at 100 percent (actual size). Use "Black and white" for the copier, or "Color" for display pages and mini books.

Popular versions

Ready-made settings for common topics.

More like this

DrillGrades 3 to 4Grades 5 to 6

Multiplication facts worksheets

Times-table drills: one table, a range of tables, squares or anchor facts, in order or shuffled.

DrillGrades 3 to 4Grades 5 to 6

Long multiplication worksheets

Multi-digit multiplication with room to show every partial product, from 2 × 1 digits up to 5 × 3.

DrillGrades 3 to 4Grades 5 to 6

Grid method multiplication

The area model: break each number into place values, fill the boxes and add them up.