Question

What must be subtracted from x^2+9+8x to make it perfect square

Answer 1

Answer:

Multiplying two binomials such as (2x + 3)(4x - 5), multiply the first terms (2x)(4x) + outside terms (2x)(-5) + inside terms (3)(4x) + last (3)(-5), so you end up with 8x^2 - 10x + 12x - 15, combine like middle terms to get 8x^2 + 2x - 15.