It seems that $ 20x^{2}+6x+9 $ cannot be factored out.
Step 1: 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 2: Multiply the leading coefficient $\color{blue}{ a = 20 }$ by the constant term $\color{blue}{c = 9} $.
$$ a \cdot c = 180 $$Step 3: Find out two numbers that multiply to $ a \cdot c = 180 $ and add to $ b = 6 $.
Step 4: All pairs of numbers with a product of $ 180 $ are:
PRODUCT = 180 | |
1 180 | -1 -180 |
2 90 | -2 -90 |
3 60 | -3 -60 |
4 45 | -4 -45 |
5 36 | -5 -36 |
6 30 | -6 -30 |
9 20 | -9 -20 |
10 18 | -10 -18 |
12 15 | -12 -15 |
Step 5: Find out which factor pair sums up to $\color{blue}{ b = 6 }$
Step 6: Because none of these pairs will give us a sum of $ \color{blue}{ 6 }$, we conclude the polynomial cannot be factored.