Question

3x^2 + 4x = -8 solve using quadratic formula

Answer 1

Use the quadratic equation to solve this (image of the quadratic equation is below)

Remember that quadratic functions are set up like so:

$ax^{2} +bx +c = 0$

To make the equation 3x² + 4x = -8 into a quadratic function you must bring -8 to the left side of the equation so it equals zero. To do this add 8 to both sides

3x² + 4x + 8= -8 + 8

3x² + 4x + 8 = 0

That means that in this equation...

a = 3

b = 4

c = 8

^^^Plug these numbers into the quadratic equation and solve  (Keep in mind that +/- is ± )

$\frac{-4+/-\sqrt{(4)^{2}-4(3)(8)}}{2(3)}$

$\frac{-4+/-\sqrt{16-96}}{6}$

$\frac{-4+/-\sqrt{-80}}{6}$

^^^There is no real solution to this equation. You must have an imaginary solution

$\frac{-4+/-i\sqrt{80}}{6}$

Simplify

$\frac{-2+/-2i \sqrt{5}}{3}$

Hope this helped!

~Just a girl in love with Shawn Mendes