Răspuns:
- [tex]$\mathbf{x = - 35 \sqrt{2} }$[/tex]
- [tex]$\mathbf{x = 2 \sqrt{7} }$[/tex]
Explicație pas cu pas:
[tex]$\mathbf{b) \: x \div ( - \sqrt{10}) = 7 \sqrt{5} }$[/tex]
[tex]$\mathbf{ - \frac{x}{ \sqrt{10} } = 7 \sqrt{5}\Longleftrightarrow \: - \frac{ \sqrt{10}x }{10} = 7 \sqrt{5} }$[/tex]
[tex]$\mathbf{x = - \frac{10}{ \sqrt{2} } \times 7 = - \frac{70}{ \sqrt{2} } }$[/tex]
[tex]$\mathbf{x = - \frac{70 \sqrt{2} }{ \sqrt{2} \sqrt{2} } = - \frac{ 70 \sqrt{2} }{2}\longrightarrow \:\boxed{\mathbf{ x = - 35 \sqrt{2} }}}$[/tex]
[tex]$\mathbf{e) \: ( - 4 \sqrt{21}) \div x = - 2 \sqrt{3} }$[/tex]
[tex]$\mathbf{ - \frac{4 \sqrt{21} }{x} = - 2 \sqrt{3} \Longleftrightarrow \: 4 \sqrt{21} = 2 \sqrt{3} x }$[/tex]
[tex]$\mathbf{2 \sqrt{3}x = 4 \sqrt{21} \Longleftrightarrow \: x = 4 \sqrt{21} \div (2 \sqrt{3} ) }$[/tex]
[tex]\boxed{\mathbf{x = 2 \sqrt{7} }}[/tex]
Bafta!
