Question

9x² = -6x+ 48. Qual o valor

Answer 1

Resposta:

Explicação passo a passo:

Subtrair 48 nos dois lados

9x²- 48 = -6x + 48 -48

9x² - 48 = -6x

Adicionar 6x nos dois lados

9x² - 48 + 6x= -6x + 6x

9x²+ 6x -48 = 0

----------------------------------------------

Resolver na fórmula quadrada

$x_{1,\:2}=\frac{-6\pm \sqrt{6^2-4\cdot \:9\left(-48\right)}}{2\cdot \:9}\\\\\sqrt{6^2-4\cdot \:9\left(-48\right)}} = 42\\\\x_{1,\:2}=\frac{-6\pm \:42}{2\cdot \:9}\\\\x_1=\frac{-6+42}{2\cdot \:9},\:x_2=\frac{-6-42}{2\cdot \:9}\\\\x = \frac{-6-42}{2\cdot \:9} : 2\\\\\\x = \frac{-6-42}{2\cdot \:9} : \frac{8}{3}\\\\x=2,\:x=-\frac{8}{3}$