Question

Resuelve lo siguiente mediante fórmula general

Answer 1

Respuesta:

x(x+3) = 5x + 3

$x^{2} + 3x = 5x+ 3\\\\x^{2} + 3x -5x- 3 =0 \\\\x^{2} -2x - 3 =0$

$\mathrm{Para\:}\quad a=1,\:b=-2,\:c=-3:\quad x_{1,\:2}=\frac{-\left(-2\right)\pm \sqrt{\left(-2\right)^2-4\cdot \:1\left(-3\right)}}{2\cdot \:1}$

$\frac{-\left(-2\right)+\sqrt{\left(-2\right)^2-4\cdot \:1\cdot \left(-3\right)}}{2\cdot \:1}$

$\frac{2+\sqrt{\left(4+12)}}{2}\\\\\\\frac{2+\sqrt{\left(16)}}{2}\\\\\frac{2+4}{2}\\\\\\\frac{6}{2}\\\\x1=3$

$\frac{-\left(-2\right)-\sqrt{\left(-2\right)^2-4\cdot \:1\cdot \left(-3\right)}}{2\cdot \:1}$

$\frac{2-\sqrt{\left4+12}}{2}\\\\\frac{2-\sqrt{\left16}}{2}\\\\\frac{2-4}{2}\\\\\frac{-2}{2}\\\\-1 \\\\x2 = -1$