Answer:
Sophia has considered the coefficient of x² as 1 in place of 16 and coefficient of x as 10 in place of - 40 in the original trinomial.
Explanation:
The given trinomial to be factorized into a perfect square is 16x² - 40x + 25.
And Sophia obtained the perfect square as (x + 5)² which gives the trinomial as x² + 10x + 25.
Therefore, Sophia's work is not correct as 16x² - 40x + 25 ≠ x² + 10x + 25.
Therefore, Sophia has considered the coefficient of x² as 1 in place of 16 and coefficient of x as 10 in place of - 40 in the original trinomial and then factorized the wrong trinomial as (x + 5)². (Answer)