Bonjour Keyzo
[tex]A=3-(\dfrac{4}{3}+\dfrac{5}{6})^2\\\\A=3-(\dfrac{8}{6}+\dfrac{5}{6})^2\\\\A=3-(\dfrac{13}{6})^2\\\\A=3-\dfrac{169}{36}\\\\A=\dfrac{108}{36}-\dfrac{169}{36}\\\\\\\boxed{A=-\dfrac{61}{36}}[/tex]
[tex]B=(-\dfrac{2}{3}-\dfrac{5}{2})\times\dfrac{4}{7}\\\\B=(-\dfrac{4}{6}-\dfrac{15}{6})\times\dfrac{4}{7}\\\\B=-\dfrac{76}{42}\\\\B=-\dfrac{2\times38}{2\times21}\\\\\\\boxed{B=-\dfrac{38}{21}}[/tex]
