factor the expression completely.
15x^2+100x+125
15x^2 + 100x + 125
First I would factor out a 5 because I know 5 can go into 15, 100 and 125.
5 (3x^2 + 20x + 25)
Now I would factor what is in the brackets.
I used the quadratic equation and got the following solutions for x:
x= -5 or x= -5/3
Therefore, the final factored form should look like:
3x^2 + 20x + 25 = 3(x - (-5))(x - (-5/3))
3x^2 + 20x + 25 = 3(x + 5)(x + 5/3)
Now multiply the 2nd bracket by 3 to simplify.
3x2 + 20x + 25 = ( x + 5 )( 3x + 5 )
So the final answer should look like:
5 (x+5)(3x+5)