[tex]\begin{gathered} We\text{ are asked to find the factors of } \\ f(x)\text{ = 5x}^2\text{ +20x + 15} \\ To\text{ factorise, we will look at the factors of 15 and 5} \\ Factors\text{ of five: \lparen5,1\rparen} \\ Factors\text{ of 15: \lparen15,1\rparen\lparen3,5\rparen} \\ f(x)\text{ = \lparen5x+5\rparen\lparen x+3\rparen} \\ 5x+5\text{ = 0} \\ x+1\text{ = 0} \\ OR\text{ x+3 = 0} \\ \end{gathered}[/tex]
Factors: (x+1) and (x+3)
Cotrrect option: A
