[tex](x + \sqrt{3} ) {}^{2} - (x - \sqrt{3} ) { }^{2} = 8 \sqrt{3} [/tex]idk how to solve it

the first step to solving this is to use a² - b² = (a - b)(a + b) to factor the expression
2√3 × 2x = 8√3
now calculate the product 
4√3x = 8√3
finally,, divide both sides of the equation by 4√3
x = 2.
this means that the correct answer to your question is x = 2.
let me know if you have any further questions
:)