\(a,\dfrac{5^2+7}{-7+9.5}=\dfrac{25+7}{-7+45}=\dfrac{16}{19}\\ \dfrac{3^4-8}{-4+3^2}=\dfrac{73}{5}\\ =\dfrac{16.5}{19.5}=\dfrac{80}{95};\dfrac{73.19}{5.19}=\dfrac{1397}{95}\\ b,\dfrac{6^2-8}{-12+4^2}=\dfrac{28}{4}=7\\ \dfrac{15-3^4}{-27+3^2}=\dfrac{11}{3}\\ =\dfrac{28.3}{4.3}=\dfrac{84}{12};\dfrac{11.4}{3.4}=\dfrac{44}{12}\)
a: \(\dfrac{5^2+7}{-7+9.5}=\dfrac{32}{2.5}=\dfrac{64}{5}\)
\(\dfrac{3^4-8}{3^2-4}=\dfrac{81-8}{9-4}=\dfrac{73}{5}\)
b: \(\dfrac{6^2-8}{4^2-12}=\dfrac{36-8}{16-12}=\dfrac{28}{4}=7=\dfrac{21}{3}\)
\(\dfrac{15-3^4}{-27+3^2}=\dfrac{15-81}{-27+9}=\dfrac{-66}{-18}=\dfrac{66}{18}=\dfrac{11}{3}\)
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