Question

3y2 - 14y=8 by factorisation
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Answer 1

$\bf \huge {3y}^{2} - 14y = 8 \\ \\ = > \rm {3y}^{2} - 14y - 8 = 0$

• NOTE :- This Can't be solved by Factorisation method. So, It has been solved by Quadratic Formula.

$\\ = > \rm \: \: y = \frac{ - b \pm \sqrt{ {b}^{2} - 4ac} }{2a} \\ \\ = > \rm \: \: \: \: \: \frac{ - ( - 14) \pm \sqrt{ {( - 14)}^{2} - 4(3)( - 8)} }{2(3)} \\ \\ = > \rm \: \: \: \: \: \frac{14 \pm \sqrt{ 196 + 96} }{6} \\ \\ = > \rm \: \: \: \: \: \frac{14 \pm \sqrt{292} }{6} \: \: = \frac{14 \pm2 \sqrt{73} }{6} \\ \\ = > \rm \: \: \: \: \: \frac{ \cancel2(7 \pm \sqrt{73} )}{ \cancel2 \times 3} = \frac{7 \pm \sqrt{73} }{3} \\ \\ \rm = > \: y \: = \boxed{ \sf\frac{7 + \sqrt{73} }{3} \: \: \: \: \: or \: \: \: \: \frac{7 - \sqrt{73} }{3} }$