Question

ayuda la he echo 20 veces y no me sale

Answer 1

Respuesta:

x = 11/8 ,  x =5

Explicación paso a paso:

3x - [(2x-5)²]/2 = (5+x)/4

[6x - (2x-5)²]/2 = (5+x)/4

4[6x - (2x-5)²] = 2(5+x)

24x - 4(2x-5)² = 10 + 2x

24x - 4(4x²-20x+25) = 10 + 2x

24x - 16x² + 80x - 100 = 10+ 2x

-16x ² +24x+80x-2x-10-100 =0

-16x²+102x -110 =0

-8x²+51x-55 =0

Formual general:

$x_{1,\:2}=\frac{-b\pm \sqrt{b^2-4ac}}{2a}$

Donde:

a= -8

b = 51

c = -55

$x_{1,\:2}=\frac{-51\pm \sqrt{51^2-4\left(-8\right)\left(-55\right)}}{2\left(-8\right)}\\\\x_{1,\:2}=\frac{-51\pm \:29}{2\left(-8\right)}$

Separa las soluciones:

$x_1=\frac{-51+29}{2\left(-8\right)},\:x_2=\frac{-51-29}{2\left(-8\right)}\\\\x=\frac{11}{8},\:x=5$