Question

Xinnn Cennn🩵🤍

想問由BC這條式子怎麼求出x？

BL = x-3
=
2
全回面第
AB = √x²² 9

Answer 1

綾

(x - 3) / 2 = x - (x^2 - 9)^0.5
=> (x^2 - 9)^0.5 = (x + 3) / 2
=> x^2 - 9 = (x^2 + 6x + 9) / 4
=> 4*x^2 - 36 = x^2 + 6x + 9
=> 3*x^2 - 6x - 27 = 0
=> x^2 - 2x - 9 = 0
=> x = [2 ± (4 + 36)^0.5] / 2
=> x = 1 ± 10^0.5

Xinnn Cennn🩵🤍

謝謝你 前面對了 但後面9移過去變-9 所以x會是5或-3 謝謝妳的幫忙
！

綾

昂對 看錯了