x² + mx + m comparing to ax² + bx + c
a = 1, b = m, c = m.
For perfect square trinomial, b² = 4ac
b² = 4ac
m² = 4*1*m
m² = 4m
m² - 4m = 0
m(m - 4) = 0
m = 0, or m - 4 = 0, m = 4.
Using m = 4,
x² + mx + m = x² + 4x + 4 = (x + 2)²
x² + mx + m = (x + 2)²
