diff --git a/arm9/examples/triangle_rotating.c b/arm9/examples/triangle_rotating.c
index 12f5dd3..3ca6dac 100644
--- a/arm9/examples/triangle_rotating.c
+++ b/arm9/examples/triangle_rotating.c
@@ -25,6 +25,10 @@ void main()
   // load identity matrices
   io_registers.a.MTX_MODE = MTX_MODE__matrix_mode__projection;
   io_registers.a.MTX_IDENTITY = 0;
+  // scale the x-axis by the ratio of the display height by the display width.
+  io_registers.a.MTX_SCALE = (192 << 12) / 256;
+  io_registers.a.MTX_SCALE = 1 << 12;
+  io_registers.a.MTX_SCALE = 1 << 12;
 
   io_registers.a.MTX_MODE = MTX_MODE__matrix_mode__position;
   io_registers.a.MTX_IDENTITY = 0;