Factor the trinomial C2 5cy 36 y2 Select the correct choic

Factor the trinomial. C^2 - 5cy - 36 y^2 Select the correct choice below and, if necessary, fill in the answer box to complete your choice. C^2 - 5cy - 36y^2 = (Factor completely.) The polynomial is prime. Click to select and enter your answers) and then click Check Answer.

Solution

We have c² -5cy -36y² = c² – 2c*5y/2 + (5y/2)² - [36y²+(5y/2)²] = (c-5y/2)² –(169y²/4) = (c-5y/2)² –(13y/2)² = [( c-5y/2) +13y/2] [( c-5y/2) -13y/2] = (c+4y)(c-9y) .

Alternate Method:

c² -5cy -36y² = c² -9cy+4cy -36y² =c(c-9y)+4y(c-9y)= (c-9y)(c+4y)