SOLUTION: 20x^2+11x-3

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Question 838082: 20x^2+11x-3
Answer by DrBeeee(684) About Me  (Show Source):
You can put this solution on YOUR website!
I assume you want to factor the equation
(1) 20x%5E2%2B11x-3+=+0
Use the quadratic equation solution
(2) %28-11%2B-sqrt%2811%5E2-4%2A20%2A%28-3%29%29%29%2F%282%2A20%29 and get
(3) x = {1/5,-3/4}
Which gives us the two factors
(4) (x-1/5)*(x+3/4)
To get the factors of (1) we need to multiply by the coefficient of x^2 or 20 as follows
(5) 20*(x-1/5)*(x+3/4) or
(6) 5*(x-1/5)*4*(x+3/4) or
(7) (5x-1)*(4x+3)
Let's see if (7) equals (1)
Is ((5x-1)*(4x+3) = 20x^2+11x-3)?
Is (20x^2 +15x -4x -3 = 20x^2+11x-3)?
Is (20x^2+11x-3 = 20x^2+11x-3)? Yes
Answer: 20x^2+11x-3 = (5x-1)*(4x+3)