If $$\Large 2x^{2}+12x+18=0$$, what is the value of x ?
 A) 3 B) 2 C) -3 D) -2

 C) -3

Given equation is

$$\Large 2x^{2}+12x+18=0$$

= $$\Large x^{2}+6x+9=0$$ [divide by 2]

= $$\Large x^{2}+3x+3x+9=0$$ [by factorisation method]

= $$\Large x \left(x+3\right)+3 \left(x+3\right)=0$$

= $$\Large \left(x+3\right) \left(x+3\right)=0$$

= $$\Large \left(x+3\right)^{2}=0$$

= x+3 = 0

= x = -3

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