Bài 3 :

a, M là trung điểm AB

=> \(A M = M B = \frac{A B}{2} = \frac{4}{2} = 2 \left(\right. c m \left.\right)\)

b, Mình không có thước đo góc nên mình tính luôn nhé.

\(\hat{A M x} + \hat{x M y} + \hat{B M y} = 18 0^{o}\) (góc bẹt)

=> \(\hat{x M y} = 6 0^{o}\)

Bài 2 :

Giải

số học sinh giỏi của lớp 6A là:

            \(\frac{2}{5}\).40=14(học sinh)

số học sinh trung bình lớp 6A là:

              \(\frac{1}{8}\) .40=5(học sinh)

       số học sinh khá lớp 6A là:

                  14+5=19(học sinh)

       số học sinh yếu của lớp 6A là:

                 40-(14+5+19)=2(học sinh          

Bài 1 :

a) )\(\frac{2}{3} - \frac{16}{3} = \frac{- 14}{3}\).

\(b , = \left(\right. \frac{3}{7} + \frac{4}{7} \left.\right) + \left(\right. - \frac{6}{19} + \frac{- 13}{19} \left.\right) = 1 - 1 = 0\)

\(c , = \frac{3}{5} . \left(\right. \frac{8}{9} - \frac{7}{9} + \frac{26}{9} \left.\right) = \frac{3}{5} . 3 = \frac{9}{5}\)

Bài 1 :

a) )\(\frac{2}{3} - \frac{16}{3} = \frac{- 14}{3}\).

\(b , = \left(\right. \frac{3}{7} + \frac{4}{7} \left.\right) + \left(\right. - \frac{6}{19} + \frac{- 13}{19} \left.\right) = 1 - 1 = 0\)

\(c , = \frac{3}{5} . \left(\right. \frac{8}{9} - \frac{7}{9} + \frac{26}{9} \left.\right) = \frac{3}{5} . 3 = \frac{9}{5}\)

Bài 1 :

a) )\(\frac{2}{3} - \frac{16}{3} = \frac{- 14}{3}\).

\(b , = \left(\right. \frac{3}{7} + \frac{4}{7} \left.\right) + \left(\right. - \frac{6}{19} + \frac{- 13}{19} \left.\right) = 1 - 1 = 0\)

\(c , = \frac{3}{5} . \left(\right. \frac{8}{9} - \frac{7}{9} + \frac{26}{9} \left.\right) = \frac{3}{5} . 3 = \frac{9}{5}\)

Bài 1 :

a) )\(\frac{2}{3} - \frac{16}{3} = \frac{- 14}{3}\).

\(b , = \left(\right. \frac{3}{7} + \frac{4}{7} \left.\right) + \left(\right. - \frac{6}{19} + \frac{- 13}{19} \left.\right) = 1 - 1 = 0\)

\(c , = \frac{3}{5} . \left(\right. \frac{8}{9} - \frac{7}{9} + \frac{26}{9} \left.\right) = \frac{3}{5} . 3 = \frac{9}{5}\)

Bài 1 :

a) )\(\frac{2}{3} - \frac{16}{3} = \frac{- 14}{3}\).

\(b , = \left(\right. \frac{3}{7} + \frac{4}{7} \left.\right) + \left(\right. - \frac{6}{19} + \frac{- 13}{19} \left.\right) = 1 - 1 = 0\)

\(c , = \frac{3}{5} . \left(\right. \frac{8}{9} - \frac{7}{9} + \frac{26}{9} \left.\right) = \frac{3}{5} . 3 = \frac{9}{5}\)

Bài 1 :

a) )\(\frac{2}{3} - \frac{16}{3} = \frac{- 14}{3}\).

\(b , = \left(\right. \frac{3}{7} + \frac{4}{7} \left.\right) + \left(\right. - \frac{6}{19} + \frac{- 13}{19} \left.\right) = 1 - 1 = 0\)

\(c , = \frac{3}{5} . \left(\right. \frac{8}{9} - \frac{7}{9} + \frac{26}{9} \left.\right) = \frac{3}{5} . 3 = \frac{9}{5}\)

Bài 1 :

a) )\(\frac{2}{3} - \frac{16}{3} = \frac{- 14}{3}\).

\(b , = \left(\right. \frac{3}{7} + \frac{4}{7} \left.\right) + \left(\right. - \frac{6}{19} + \frac{- 13}{19} \left.\right) = 1 - 1 = 0\)

\(c , = \frac{3}{5} . \left(\right. \frac{8}{9} - \frac{7}{9} + \frac{26}{9} \left.\right) = \frac{3}{5} . 3 = \frac{9}{5}\)

Bài 1 :

a) )\(\frac{2}{3} - \frac{16}{3} = \frac{- 14}{3}\).

\(b , = \left(\right. \frac{3}{7} + \frac{4}{7} \left.\right) + \left(\right. - \frac{6}{19} + \frac{- 13}{19} \left.\right) = 1 - 1 = 0\)

\(c , = \frac{3}{5} . \left(\right. \frac{8}{9} - \frac{7}{9} + \frac{26}{9} \left.\right) = \frac{3}{5} . 3 = \frac{9}{5}\)