Question

(корень) 15x (в степени 2) -x+12=4x

Answer 1

$\sqrt{15x^{2}-x+12 } =4x\\\\(\sqrt{15x^{2}-x+12 } )^{2} =(4x)^{2} \ ; \ 4x>0 \ \Rightarrow \ x>0\\\\15x^{2}-x+12=16x^{2}\\\\x^{2} +x-12=0\\\\Teorema \ Vieta:\\x_{1}=3\\\\x_{2}=-4<0-neyd\\\\Otvet:\boxed3$