Question

c-5X (3+ 2x ) = 3(x+5)​

Answer 1

Respuesta:

$c-5x\left(3+2x\right)=3\left(x+5\right)\quad :\quad x=-\frac{9+\sqrt{10c-69}}{10},\:x=-\frac{9-\sqrt{10c-69}}{10}$

Explicación paso a paso:

$c-5x\left(3+2x\right)=3\left(x+5\right)$

$c-15x-10x^2=3x+15$

$c-15x-10x^2-15=3x+15-15$

$c-15x-10x^2-15=3x$

$c-15x-10x^2-15-3x=3x-3x$

$-10x^2-18x+c-15=0$

$x_{1,\:2}=\frac{-\left(-18\right)\pm \sqrt{\left(-18\right)^2-4\left(-10\right)\left(c-15\right)}}{2\left(-10\right)}$

$x_{1,\:2}=\frac{-\left(-18\right)\pm \:2\sqrt{10c-69}}{2\left(-10\right)}$

$x_1=\frac{-\left(-18\right)+2\sqrt{10c-69}}{2\left(-10\right)},\:x_2=\frac{-\left(-18\right)-2\sqrt{10c-69}}{2\left(-10\right)}$

$x=-\frac{9+\sqrt{10c-69}}{10},\:x=-\frac{9-\sqrt{10c-69}}{10}$