Answers

2016-02-21T10:32:57+05:30
First of all arrange the quadratic equation degree wise . Ex - : -17x + 30 + x^2 = 0 should be arranged as x^2 - 17x + 30 = 0 Now prime factorise constant terms : 30 = 2 * 3 * 5 Now by hit and triel group the factors into two and check if sum is 17 . Ex : Hit and Trials : ( 2 * 3 ) * 5 = 6 * 5 but 6 + 5 = 11 ( 2 * 5 ) * 3 = 10 * 5 but 10 + 5 = 15 ( 3 * 5 ) * 2 = 15 * 2 & 15 + 2 = 17 ( So this must be our splitting pair ) but we have -17 and not + 17 , accordingly we will choose -2 and -15 Since , -2 + -15 = -17 & -2 * -15 = 30 So x^2 -17x + 30 = 0 => x^2 - 2x - 15x + 30 = 0 => x ( x - 2 ) -15 ( x - 2 ) = 0 => ( x - 15 ) ( x - 2 ) = 0 Do a lot of practice , and it will come naturally to you .
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