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