SOLUTION: I had to solve a quadratic equation by factoring and I recived it back as incorect. I dont know what I did wrong...could someone please explain this to me and show the correct step

Question 112700: I had to solve a quadratic equation by factoring and I recived it back as incorect. I dont know what I did wrong...could someone please explain this to me and show the correct steps if possible. I did not get 2 solutions for x and I cant figure out how to do this.
Thanks so much.
3x^2+11x-20=0
3x^2+15x-4x-20=0
3x(x+15)-4(x+5)=0
(3x-4)(x+5=0)

Found 2 solutions by jim_thompson5910, MathLover1:
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
I'm going to start where you left off

or Set each factor equal to zero

or Solve for x in each case

So our solution is or
Answer by MathLover1(20849) (Show Source): You can put this solution on YOUR website!

....well done up to here...
now, the product above will be equal to if one or both factors are equal to
let find out what are values for :

if ........first solution

if .........second solution

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