25% : ( 10,3-8,9 ) - 75%
\(=\frac{1}{4}:\frac{7}{5}-\frac{3}{4}=\frac{5}{28}-\frac{3}{4}=-\frac{4}{7}\)
25%:1,4-75%
1/4:7/5-3/4
1/4.5/7-3/4
5/28-3/4
-4/7
đúng thì tích
mình ko gh đề nha:
\(=\frac{1}{4}:\left(\frac{103}{10}-\frac{89}{10}\right)-\frac{3}{4}\)
\(=\frac{1}{4}:\left(\frac{103-89}{10}\right)-\frac{3}{4}\)
\(=\frac{1}{4}:\frac{7}{5}-\frac{3}{4}\)
\(=\frac{1}{4}.\frac{5}{7}-\frac{3}{4}\)
\(=\frac{5}{28}-\frac{21}{28}\)
\(=\frac{5-21}{28}\)
\(=\frac{-16}{28}=\frac{-4}{7}\)
\(x = {-b \pm \sqrt{b^2-4ac} \over 2a}\)