Question

What are the possible values of x in 8x2 + 4x = -1?

Answer 1

Answer:

The possible values of x are:

x= $\frac{-1+\sqrt{3}}{4} \,\,or\,\, x= 0.18$

and

x= $\frac{-1-\sqrt{3}}{4} \,\, or \,\, x= -0.68$

Step-by-step explanation:

$8x^2+4x+1=0$

Using Quadratic formula to solve this equation:

$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}\\a = 8 \,\, b = 4\,\, c = -1\\Putting \,\, values \,\, in \,\, the\,\, equation\\x= \frac{-4\pm\sqrt{(4)^2-4(8)(-1)}}{2(8)}\\x= \frac{-4\pm\sqrt{16+32}}{16}\\x= \frac{-4\pm\sqrt{48}}{16}\\x= \frac{-4+ \sqrt{48}}{16} \,\, and \,\, x= \frac{-4- \sqrt{48}}{16}\\x= \frac{-1+ \sqrt{3}}{4} \,\, and \,\, x= \frac{-1- \sqrt{3}}{4}$

The possible values of x are:

x= $\frac{-1+\sqrt{3}}{4} \,\,or\,\, x= 0.18$

and

x= $\frac{-1-\sqrt{3}}{4} \,\, or \,\, x= -0.68$