What’s on the Similar Triangles poster
The rule, 4 worked examples, and the mistake everyone makes.
- Similar figures have equal corresponding angles and proportional corresponding sides.
- AA · SSS ratios · SAS ratio
- AA = two angles equal
- Scale factor k = lengths × k
- Area = × k²
- Volume = × k³
- Common mistake: doubling lengths doubles area → it quadruples it
Congruent is the special case of similar where k = 1.
Questions about the Similar Triangles poster
- What’s on the Similar Triangles poster?
- The rule, 4 worked examples, and the mistake everyone makes. Similar figures have equal corresponding angles and proportional corresponding sides.; AA · SSS ratios · SAS ratio; AA = two angles equal; Scale factor k = lengths × k; Area = × k²; Volume = × k³; Common mistake: doubling lengths doubles area → it quadruples it. Congruent is the special case of similar where k = 1.
- Who is the Similar Triangles poster for?
- Similar Triangles is filed under 9th Grade (ages 14–15), so it matches what that year asks a child to remember. It is equally useful to an older student revisiting math, and to the parent or teacher answering the question at the kitchen table.
- When should you use the Similar Triangles poster?
- Write the similarity statement with the vertices in matching order. It tells you which sides pair up. A wall chart earns its place by being glanceable from where the work is happening, so Similar Triangles belongs on the wall where that math work actually happens, within glancing distance, rather than filed away.
- What other posters go with Similar Triangles?
- Triangle Theorems, Absolute Value Equations and Arithmetic Sequences sit alongside Similar Triangles in the 9th Grade set. Printed together they make a wall rather than a single sheet, which is how a reference set actually gets used.Triangle TheoremsAbsolute Value EquationsArithmetic Sequences
- Is the Similar Triangles poster free to download and print?
- Yes. Similar Triangles downloads as a free PDF with no account, no email and no watermark, like everything else in the 9th Grade set. Print as many copies as you like for a home, a classroom, a library or a tutoring group; reselling the file is the only thing the licence rules out.Read the licence
- What size does the Similar Triangles poster print at?
- Similar Triangles is a vector PDF laid out for US Letter, and prints on A4 with Fit to page — the same file, no separate download. Because every mark on it is drawn rather than photographed, it stays sharp enlarged to A3, A2 or A1 at a copy shop. Colour carries emphasis only, so a greyscale print of Similar Triangles loses nothing.Printing guide
Related posters
Charts that sit alongside Similar Triangles on the same wall.
Browse every 9th Grade poster, or start from the full catalogue.