Question

(x+√3)² -10=x² - (√3+2)²

Answer 1

$\displaystyle (x+ \sqrt{3} )^2-10=x^2-( \sqrt{3} +2)^2 \\ x^2+2 \cdot x \cdot \sqrt{3} + \sqrt{3} ^2-10=x^2-( \sqrt{3} ^2+2 \cdot \sqrt{3} \cdot 2+2^2) \\ x^2+2x \sqrt{3} +3-10=x^2-3-4 \sqrt{3} -4 \\ x^2-x^2+2x \sqrt{3} =-3-4 \sqrt{3} -4-3+10 \\ 2x \sqrt{3} =-4 \sqrt{3} \\ x=- \frac{4 \sqrt{3} }{2 \sqrt{3} } \\ x=-2$