Question

Giúp mình nhé. Tìm số nguyên x

1. \(\frac{x-2}{15}\) = \(\frac{9}{5}\)

2. \(\frac{14}{8}\) =\(\frac{x-1}{4}\)

3. Cho hai góc kề bù góc xOt và góc tOy. Tính gõ xOt khi biết 3xOt= 2tOy

Answer 1

1) \(\frac{x-2}{15}=\frac{9}{5}\\ \Leftrightarrow x-2=\frac{9.15}{5}\\ \Leftrightarrow x-2=27\\ \Leftrightarrow x=27+2=29\)

2) \(\frac{14}{8}=\frac{x-1}{4}\\ \Leftrightarrow\frac{7}{4}=\frac{x-1}{4}\\ \Leftrightarrow7=x-1\\ \Leftrightarrow x=8\)

3) \(\left\{{}\begin{matrix}\widehat{xOt}+\widehat{tOy}=180^o\\3.\widehat{xOt}=2.\widehat{tOy}\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}\widehat{xOt}+\widehat{tOy}=180^o\\\widehat{tOy}=1,5.\widehat{xOt}\end{matrix}\right.\)

\(\Leftrightarrow\left\{{}\begin{matrix}\widehat{xOt}+1,5.\widehat{xOt}=180^o\\\widehat{tOy}=1,5.\widehat{xOt}\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}\widehat{xOt}=72^o\\\widehat{tOy}=180^o-72^o=108^o\end{matrix}\right.\)