Factor the trinomial. 5y4 + 12y3 - 9y2

y²(y + 3)(5y - 3)

Step-by-step explanation:

Given

5 + 12y³ - 9y² ← factor out y² from each term

= y²(5y² + 12y - 9) ← factor the quadratic

Consider the factors of the product of the y² term and the constant term which sum to give the coefficient of the y- term

product = 5 × - 9 = - 45 and sum = + 12

The factors are + 15 and - 3

Use these factors to split the y- term

5y² + 15y - 3y - 9 ( factor the first/second and third/fourth terms )

= 5y(y + 3) - 3(y + 3) ← factor out (y + 3) from each term

= (y + 3)(5y - 3), so

5y² + 12y - 9 = (y + 3)(5y - 3)

Then

5 + 12y³ - 9y² = y²(y + 3)(5y - 3) ← in factored form