Trinomials can be factored three different ways: By grouping, With quadratic formula, Completing the square.
Quadratic formula hard to memorize but always works. Its template is:
![x = \frac{ - b \pm \sqrt{ {b}^(2) - 4ac } }{2a}](https://img.qammunity.org/2019/formulas/mathematics/high-school/oir2t9c2ju7q7s3ffwhi0ht2uvyy42bmg2.png)
To make quadratic formula work, we need to put the equation into the standard form. In this case, it's already in that form.
![a=4, b=23, c=-6](https://img.qammunity.org/2019/formulas/mathematics/middle-school/3hr4brw3ocfhwmjd3vfxxxu6po8evozb5v.png)
.
When we plug them in:
![x = \frac{- 23 \pm \sqrt{ {23}^(2) - 4 * 4 * ( - 6) } }{2 * 4}](https://img.qammunity.org/2019/formulas/mathematics/middle-school/6vsa7kcpzndcq8un5m3p79n8rjoe3ip74b.png)
Simplify:
![x = ( - 23 \pm√(529 + 96) )/(8)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/8riqtkqk7jstlwq5s5d5wbih5r9rj2oiyz.png)
![x = ( - 23\pm √(625) )/(8)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/k2dhd3btkxh1uwaiwiz3d9voyruzhsia6z.png)
![x = ( - 23 \pm25 )/(8)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/bfkrpxonb8jn3sf7is8hh8epggltvq031p.png)
Branch out the plus-minus sign:
![x = ( - 23 + 25)/(8) \: \: \: \: \:x = ( - 23 - 25)/(8)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/v12pcqfkcfyktu7curajf0psie0y5tz4xw.png)
![x = (2)/(8) \: \: \: \: \:x = ( - 48)/(8)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/t8jdq79f758bqv2bj2mpl76qbb9qqo6efl.png)
![x = (1)/(4) \: \: \: \: \:x = - 6](https://img.qammunity.org/2019/formulas/mathematics/middle-school/xaqxn87btd1xj6869pory8wq6exz1425xq.png)
So it's roots are
![(1)/(4) , -6](https://img.qammunity.org/2019/formulas/mathematics/middle-school/kmgjtn6txi257i0j2irhatrd9yyho0kgux.png)
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Roots of a polynomial are the values which made the equation equal to 0. To make this, we need to write the factored form as
![(x - (1)/(4) )(x + 6)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/zi0bxihy6r4vczgbxi2s30gubq6mmqtg4g.png)
And because
![- (1)/(4)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/y429r1idh6xb5y6h3jdlhdfr7vlccoxwsf.png)
is a fraction, we need to get rid of it. We can do this by multiplying the left side with 4 and our final answer would be
![(4x - 1)(x + 6)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/iwwtm3nd1bz5pwlj338mkd8womrx0qtgqc.png)
.