Question

Rezolvati ecuatia:4x^2-9x=0

Answer 1

x(4x-9)=0 
Nu se poate face altfel.

Answer 2

$M1)4{x}^{2}-9x=0$

$x(4x-9)=0$

$=>x_{1}=0$

$=>4x-9=0=>4x=9=>x_{2}=\frac{9}{4}$

$M2)4 {x}^{2} - 9x = 0$

$a = 4$

$b = - 9$

$c = 0$

$\Delta = {b}^{2} - 4ac$

$\Delta = {( - 9)}^{2} - 4 \times 4 \times 0$

$\Delta = 81$

$x_{1,2}=\frac{-b\pm\sqrt{\Delta}}{2a}$

$x_{1,2}=\frac{-( - 9)\pm\sqrt{81}}{2 \times 4}$

$x_{1,2}=\frac{9\pm9}{8}$

$x_{1}=\frac{9 + 9}{8}$

$x_{1}=\frac{18}{8}$

$x_{1}=\frac{9}{4}$

$x_{2}=\frac{9 - 9}{8}$

$x_{2}=\frac{0}{8}$

$x_{2}=0$