Question

Розв’язати рівняння(Помогите)

Answer 1

$\displaystile\bf\\1)\\\\(x+6)^{2} -79=(x+5)(x-5)\\\\x^{2} +2\cdot x\cdot 6+6^{2} -79=x^{2} -5^{2} \\\\x^{2} +12x+36-79=x^{2} -25\\\\x^{2} +12x-x^{2} =-25-36+79\\\\12x=18\\\\\boxed{x=1,5}\\\\\\2)\\\\7x^{3} -63x=0\\\\7x\cdot(x^{2} -9)=0\\\\7x\cdot(x^{2} -3^{2} )=0\\\\7x\cdot(x-3)\cdot(x+3)\\\\\\\left[\begin{array}{ccc}x=0\\x-3=0\\x+3=0\end{array}\right\\\\\\\left[\begin{array}{ccc}x_{1} =0\\x_{2} =3\\x_{3} =-3\end{array}\right\\\\\\Otvet \ : \ 0 \ : \ -3 \ ; \ 3$