Question

Помогите пожалуйста
а) 2х²=0,98
б) у²-6=19
в) √х-3=8​

Answer 1

$1)2x^{2}=0,98\\\\x^{2}=0,49\\\\x_{1,2}=\pm\sqrt{0,49}=\pm0,7\\\\\boxed{x_{1} =-0,7;x_{2}=0,7}\\\\\\2)y^{2}-6=19\\\\y^{2}=25\\\\y_{1,2}=\pm\sqrt{25}=\pm5\\\\\boxed{y_{1}=-5;y_{2} =5}$

$3)\sqrt{x-3}=8\\\\(\sqrt{x-3})^{2}=8^{2}\\\\x-3=64\\\\x=67\\\\Proverka:\\\\\sqrt{67-3}=8\\\\\sqrt{64}=8\\\\8=8-verno\\\\Otvet:\boxed{67}$