Answer:
it is a perfect square
Explanation:
given
m² - 16m + 64
consider the factors of the constant term (+ 64) which sum to give the coefficient of the m- term (- 16)
the factors are - 8 and - 8 , since
- 8 × - 8 = + 64 and - 8 - 8 = - 16
use these factors to split the m- term
m² - 8m - 8m + 64 ( factor the first/second and third/fourth terms )
m(m - 8) - 8(m - 8) ← factor out (m - 8) from each term
(m - 8)(m - 8)
Then
m² - 16m + 64 = (m - 8)(m - 8) = (m - 8)² ← a perfect square