Pythagorean Theorem | Math Mystery Worksheets | Grades 7–9 | Missing Sides and Distance

Ten detective cases work the Pythagorean theorem from every angle it appears in — each page is one case and one skill, so students solve each problem, write the answer on the line beside it, match it to a suspect, and cross suspects off until one is left standing. This no-prep, printable, self-checking Math Mystery keeps 7th, 8th and 9th graders engaged and works for math centers, morning work, homework, early finishers, substitute/relief days, spiral review, and test prep. Some answers are whole numbers and some round to the nearest tenth.

Quick Details

Skill: The Pythagorean theorem · Grades: 7–9 · Format: 10 mysteries, one per skill + full answer keys (printable PDF) · Theme: School detective

The 10 Mysteries

The Roof Truss Riddle — Every truss in the school hall came back with its long side rubbed out, so students find the missing sloping side.

The Fence Post Puzzle — The longest side is given, so students work backwards to a missing leg.

The Screen Size Swap — A screen is sold by its diagonal, and every label in the media room is gone.

The Map Grid Mix-Up — Students read coordinates off each grid and find the distance between two points.

The Site Plan Shuffle — No diagram is given: students sketch the right triangle for each job themselves.

The Packed Crate Plot — The diagonal runs corner to corner through a three-dimensional crate.

The Camp Tent Tangle — A dashed line splits each tent in two, and the height has to come out of the halves.

The Skate Ramp Racket — The sloping edges have been erased from the ramp plans.

The Pennant Panic — Students find the missing side first, then the perimeter, so the trim can be cut.

The Sail Loft Switch — Missing side first, then the area of each sail.

Why Teachers Love It

Zero prep — print and teach. The built-in answer keys make every case self-checking, so students get instant feedback and stay motivated. Because each page is a different application — leg, hypotenuse, coordinate distance, 3D diagonal, two-step area and perimeter — one file covers the whole unit instead of drilling the same problem ten times.

Skills Covered

Finding the hypotenuse, finding a missing leg, the distance between two points on a coordinate grid, diagonals through three-dimensional solids, splitting an isosceles figure into right triangles, sketching a diagram from a word problem, rounding to the nearest tenth, and two-step problems that end in perimeter or area — plus logical reasoning and deductive elimination as students rule suspects out clue by clue.

What's Included

Printable one-page mystery worksheets, labelled diagrams, suspect line-ups, complete answer keys with the villain marked, and student instructions — all in one PDF.

Best Used For

Pythagorean theorem practice in math centers, morning work, homework, early finishers, substitute/relief days, spiral review, and end-of-unit test prep for grades 7–9.

More From This Line

Browse every Math Mystery pack, or take it further with Right Triangle Trigonometry and Volume of Cylinders, Cones and Spheres.