It seems that $ 4x^{2}+29x+105 $ 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 $\color{blue}{ a = 4 }$ by the constant term $\color{blue}{c = 105} $.
$$ a \cdot c = 420 $$Step 3: Find out two numbers that multiply to $ a \cdot c = 420 $ and add to $ b = 29 $.
Step 4: All pairs of numbers with a product of $ 420 $ are:
PRODUCT = 420 | |
1 420 | -1 -420 |
2 210 | -2 -210 |
3 140 | -3 -140 |
4 105 | -4 -105 |
5 84 | -5 -84 |
6 70 | -6 -70 |
7 60 | -7 -60 |
10 42 | -10 -42 |
12 35 | -12 -35 |
14 30 | -14 -30 |
15 28 | -15 -28 |
20 21 | -20 -21 |
Step 5: Find out which factor pair sums up to $\color{blue}{ b = 29 }$
Step 6: Because none of these pairs will give us a sum of $ \color{blue}{ 29 }$, we conclude the polynomial cannot be factored.