Question

solve the underlined one

Answer 1

The equation is

$3 {x}^{2} - x - 2 = 0$

Divide the equation by coefficient of x square.

$\frac{3 {x}^{2} - x - 2 }{3} = 0 \\ \\ {x}^{2} - \frac{x}{3} - \frac{2}{3} = 0$

Transfer the number without algebra to another side.

${x}^{2} - \frac{x}{3} = \frac{2}{3}$

Add (1/2 × coefficient of x)^2 to both sides..

${x}^{2} - \frac{x}{3} + \frac{1}{36} = \frac{2}{3} + \frac{1}{36} \\ \\ \frac{36 {x}^{2} - 12x + 1 }{36} = \frac{24 + 1}{36} \\ \\ 36 {x}^{2} - 12x + 1 = 25$

Express the equation in LHS as a whole square equation.

${(6x)}^{2} - 2 \times 6x \times 1 + {(1)}^{2} = 25 \\ {(6x - 1)}^{2} = 25$

Now find the solution.

$6x - 1 = \sqrt{25} = 5 \\ 6x = 5 + 1 = 6 \\ x = \frac{6}{6} \\ x = 1 \\ \\ or \\ \\ 6x - 1 = \sqrt{25} = - 5 \\ 6x = - 5 + 1 = - 4 \\ x = \frac{ - 4}{6} \\ x = \frac{ - 2}{3}$

Hope this helps you....

Be Brainly!!!!

Answer 2

Answer:

my friend has given you answer