Question

help minnhf câu 12 13 14 15 ;99

Answer 1

12: 

\(=\dfrac{-23}{11}-\dfrac{3}{11}=\dfrac{-23-3}{11}=-\dfrac{26}{11}\)

13: \(=\dfrac{23+17}{9}=\dfrac{40}{9}\)

14: \(=\dfrac{9+11}{8}=\dfrac{20}{8}=\dfrac{5}{2}\)

15: \(=\dfrac{-1-5}{2}=-\dfrac{6}{2}=-3\)