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 $\color{blue}{ a = 14 }$ by the constant term $\color{blue}{c = 14} $.
$$ a \cdot c = 196 $$Step 3: Find out two numbers that multiply to $ a \cdot c = 196 $ and add to $ b = -53 $.
Step 4: All pairs of numbers with a product of $ 196 $ are:
PRODUCT = 196 | |
1 196 | -1 -196 |
2 98 | -2 -98 |
4 49 | -4 -49 |
7 28 | -7 -28 |
14 14 | -14 -14 |
Step 5: Find out which factor pair sums up to $\color{blue}{ b = -53 }$
PRODUCT = 196 and SUM = -53 | |
1 196 | -1 -196 |
2 98 | -2 -98 |
4 49 | -4 -49 |
7 28 | -7 -28 |
14 14 | -14 -14 |
Step 6: Replace middle term $ -53 x $ with $ -4x-49x $:
$$ 14x^{2}-53x+14 = 14x^{2}-4x-49x+14 $$Step 7: Apply factoring by grouping. Factor $ 2x $ out of the first two terms and $ -7 $ out of the last two terms.
$$ 14x^{2}-4x-49x+14 = 2x\left(7x-2\right) -7\left(7x-2\right) = \left(2x-7\right) \left(7x-2\right) $$