Step 1 :
After factoring out $ 2 $ we have:
$$ 4x^{2}+22x+10 = 2 ( 2x^{2}+11x+5 ) $$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 $\color{blue}{ a = 2 }$ by the constant term $\color{blue}{c = 5} $.
$$ a \cdot c = 10 $$Step 4: Find out two numbers that multiply to $ a \cdot c = 10 $ and add to $ b = 11 $.
Step 5: All pairs of numbers with a product of $ 10 $ are:
| PRODUCT = 10 | |
| 1 10 | -1 -10 |
| 2 5 | -2 -5 |
Step 6: Find out which factor pair sums up to $\color{blue}{ b = 11 }$
| PRODUCT = 10 and SUM = 11 | |
| 1 10 | -1 -10 |
| 2 5 | -2 -5 |
Step 7: Replace middle term $ 11 x $ with $ 10x+x $:
$$ 2x^{2}+11x+5 = 2x^{2}+10x+x+5 $$Step 8: Apply factoring by grouping. Factor $ 2x $ out of the first two terms and $ 1 $ out of the last two terms.
$$ 2x^{2}+10x+x+5 = 2x\left(x+5\right) + 1\left(x+5\right) = \left(2x+1\right) \left(x+5\right) $$