Question

solve this question by both methods, first by method of completing the squares and then by using quadratic formula: 1. √5x2 - 3√6x - √20 = 0

Answer 1

Given 3x2−5x+2=0

Here, the coefficient of x2 is 3 and it is not a perfect square.

∴ Multiply the equation throughout by 3.

⇒(3x2−5x+2=0)×3∴9x2−15x+6=0

Now, half of the coefficient of x is 25.∴b=25 and b2=(25)2

So, 9x2−15x+(25)2−(25)2+6=0,(3x)2−15x+(25)2=(25)2−6

(3x−25)2=425−6=41