Question

Solve for x: 8x-4(-5x-2)=12x

Answer 1

Answer:

$\frac{-1\±\sqrt{21} }{10}$

Step-by-step explanation:

First let's multiply out the equation

$8x-4(-5x-2)=12x$

$-40x^2-16x+20x+8=12x$

$-40x^2-8x+8$

We can't factor so I will use the quadratic formula

$\frac{-b\±\sqrt{b^2-4ac} }{2a}$

$\frac{8\±\sqrt{(-8)^2-4(-40)(8)} }{2(-40)}$

$\frac{8\±\sqrt{64+1280} }{-80}$

$\frac{8\±\sqrt{1344} }{-80}$

$\frac{8\±\ 8 \sqrt{21} }{-80}$

$\frac{-1\±\sqrt{21} }{10}$

Answer 2

Answer:

X= -1/2

Step-by-step explanation:

8x-4(-5x-2)=12x

8x+20x+8=12x

28x+8=12x

8=-16x

-1/2=x