1
Start your expression
Add 1 blue x² tile and an even number of green x tiles (try 6).
2
Arrange into an L
Place the x² in the top-left corner. Split your x-tiles evenly — half along the right edge, half along the bottom.
3
Find the missing corner
There's a gap in the bottom-right. How many 1-tiles fill it perfectly? That number is (b/2)².
4
Complete the square!
Fill in the corner and the hint box confirms your perfect square — and shows you the factored form.