Step 1 :
After factoring out $ 2y $ we have:
$$ 24y^{3}+6y^{2}-20y = 2y ( 12y^{2}+3y-10 ) $$Step 2 :
Step 2: Identify constants $ a $ , $ b $ and $ c $.
$ a $ is a number in front of the $ x^2 $ term $ b $ is a number in front of the $ x $ term and $ c $ is a constant. In this case:
Step 3: Multiply the leading coefficient $\color{blue}{ a = 12 }$ by the constant term $\color{blue}{c = -10} $.
$$ a \cdot c = -120 $$Step 4: Find out two numbers that multiply to $ a \cdot c = -120 $ and add to $ b = 3 $.
Step 5: All pairs of numbers with a product of $ -120 $ are:
PRODUCT = -120 | |
-1 120 | 1 -120 |
-2 60 | 2 -60 |
-3 40 | 3 -40 |
-4 30 | 4 -30 |
-5 24 | 5 -24 |
-6 20 | 6 -20 |
-8 15 | 8 -15 |
-10 12 | 10 -12 |
Step 6: Find out which factor pair sums up to $\color{blue}{ b = 3 }$
Step 7: Because none of these pairs will give us a sum of $ \color{blue}{ 3 }$, we conclude the polynomial cannot be factored.