Question

me ajudem nessa por favor:
4x² + 9 = 12x

Answer 1

4x² - 12x + 9 = 0
/\ = (-12)² - 4.4.9
/\ = 144 - 144
/\ = 0
x' = x" = -b/2a
x' = x" = -(-12)/2.4
x' = x" = 12/8 = 12:4/8:4 = 3/2

Answer 2

$4 x^{2} +9=12x \\ \\ 4 x^{2} +9-12x=0 \\ \\ 4 x^{2} -12x+9=0$

Discriminante:

$\Delta=b\²-4*a*c \to \Delta=(-12)\²-4*4*9 \\ \\ \Delta=(-12)\²-144 \\ \\ \Delta=144-144 \\ \\ \Delta=0$

Bhaskara
$x_{1,2}= \frac{-b\± \sqrt{\Delta}}{2*a} \to \frac{12\± \sqrt{0} }{2*4} \\ \\ x_{1,2}= \frac{12\±0}{8} \\ \\ x_{1,2}= \frac{12}{8}$

Simplificando o Resultado
$\frac{12}{8}$÷2 = $\frac{6}{4}$÷2 = $\frac{3}{2}$