-1- -3. (2)(3) 21 21 ,ajutor

[tex]\bf =- \bigg(\dfrac{^{7)}7}{\ \ 3}-\dfrac{25}{21}\bigg):\dfrac{74}{21}=-\dfrac{49-25}{\not21}\cdot\dfrac{\not21}{74}=-\dfrac{\ \ 24^{(2}}{74}=-\dfrac{12}{37}[/tex]