Answer:
The square of a binomial pattern
Explanation:
Given
9x² - 30x + 25
Consider the factors of the product of the coefficient of the x² term and the constant term which sun to give the coefficient of the x- term.
product = 9 × 25 = 225 and sum = - 30
The factors are - 15 and - 15
Use these factors to split the x- term
9x² - 15x - 15x + 25 ( factor the first/second and third/fourth terms )
= 3x(3x - 5) - 5(3x - 5) ← factor out (3x - 5) from each term
= (3x - 5)(3x - 5)
= (3x - 5)² ← the square of a binomial pattern