Which shows a perfect square trinomial?

Both (m + n) 2 and 36 are perfect squares, and 12 (m + n) is twice the product of (m + n) and 6. Since the middle term is positive, the pattern is (a + b) 2 = a 2 + 2ab + b 2. Place the x2 tile, 4 x-tiles and 4 1-tiles in the grid. Fill the outside sections of the grid with x-tiles and 1-tiles that complete the pattern.