[tex]a) \frac{ - 23 - 4}{ - 28 + 19} = \frac{ - 27}{ - 9} = 3[/tex]
[tex]b) \frac{13 - 49}{ - 6} \times 5 = \frac{ - 36}{ - 6} \times 5 = 6 \times 5 = 30[/tex]
[tex]c) \frac{25 - ( - 3)}{ - 2 \times ( - 15 + 8)} = \frac{28}{ - 2 \times - 7} = \frac{28}{14} = 2[/tex]
[tex]d) \frac{( - 5 {)}^{2} - ( - 1 {)}^{2} }{( - 2 {)}^{3} + 2 } = \frac{25 - 1}{ - 8 + 2} = \frac{24}{ - 6} = - 4[/tex]
