Question

Resolva a equação a seguir do 2 grau sendo U=R: 5t²-9t+4=0

Answer 1

$5t^2-9t+4=0$

$\Delta=b^2-4ac=(-9)^2-4(5)(4)=81-80=1$

$x_1= \frac{-b+ \sqrt{\Delta}}{2a}= \frac{-(-9)+ \sqrt{1}}{2(5)}= \frac{9+1}{10}= \frac{10}{10}=1$

$x_1= \frac{-b- \sqrt{\Delta}}{2a}= \frac{-(-9)- \sqrt{1}}{2(5)}= \frac{9-1}{10}= \frac{8}{10}= \frac{4}{5}$

Logo, S={$\frac{4}{5},1$}.