Is this right?

[Dominic]

Factor: 3a^2 + 9a + 6.

My answer is :

3(a + 2)(a + 3)

Is this correct?

 

[Guest]

You can check it by multiplying it out.

3(a + 2)(a + 3)
= 3(a^2 + 3a + 2a + 6)
= 3(a^2 + 5a + 6)
= 3a^2 + 15a + 18

That's not 3a^2 + 9a + 6.

 

[Guest]

3a^2 + 9a + 6

try using the quadratic formula to factor that out, or complete the square.

 

[Matt]

Hi Dominic,

Factor: 3a^2 + 9a + 6.

My answer is :

3(a + 2)(a + 3)

Is this correct?

Almost. That last 3 should be a 1:

. . . .

 

[Dominic]

Thanks guys.