Question

5. Se x = 2, y= 5 e z = - 3 determine o valor numérico de - 3x² + 2y - 2 z/y² + 7 z

Answer 1

$V=-3 x^{2} + 2y - \frac{2z}{y^{2} }+ 7z \\ V = -3 (2)^{2} + 2 (5) - \frac{2 (-3)}{ (5)^{2} } \\ V = -3 (4) + 10 - ( \frac{-6}{25} ) \\ V = -12 +10 + \frac{6}{25} \\ V= \frac{(25)-12+(25)10+ 6}{25} \\ V=-300+250+6 \\ V=-300+256 \\ V=-44$