Question

Medal!!!
Solve -3x2 - 4x - 4 = 0.

Answer 1

I have this so far:
a = -3 b = -4 c = -4

x = 4 +- √(-4)^2 – 4 * -3 * -4 / 2(-3)

x = 4 +- √-32 / -6

x = 4 +- √-1 * √4 *√8 / -6

Answer 2

you cant fail if you use the quadratic formula thing

Answer 3

i can tell it will not be a real number solution

Answer 4

I just can't remember what to do next.

Answer 5

\[x = \frac{ 4 \pm \sqrt{16 - 4*(-3)*(-4)} }{ -6 }\]

Answer 6

simplify the root

Answer 7

\[x = \frac{ 4 \pm \sqrt{-32} }{ -6 }\]

Answer 8

recall
\[\sqrt{-32} = \sqrt{-1 * 32} = \sqrt{-1}\sqrt{32} = i *\sqrt{16*2} = 4i*\sqrt{2}\]

Answer 9

Yes, i have gotten that far i have\[x = 4 +- √-1 * √4 *√8 / -6\]

Answer 10

ok, remember i = square root of -1

Answer 11

\[x = \frac{ 4 \pm 4i \sqrt{2} }{ -6 }\]

Answer 12

you can simplify it a bit more, by dividing everything by 2

Answer 13

\[x = \frac{ 2 \pm 2i \sqrt{2} }{ -3 }\]

Answer 14

\[x = \frac{ -2 }{ 3 } \pm \frac{ -2i }{ 3 }\sqrt{2}\]

Answer 15

Do you understand everything?

Answer 16

I think

Answer 17

You got to this right?
\[x = \frac{ 4 \pm \sqrt{-1}\sqrt{4}\sqrt{8} }{ -6 }\]

Answer 18

replace, square root of -1 with imaginary number i.
\[\sqrt{8}\sqrt{4} = \sqrt{32} = \sqrt{16}\sqrt{2} = 4\sqrt{2}\]
Instead of root 8 times root 4, use root 16 times root 2

Answer 19

ok

Answer 20

@DanJS Could you help me with another?

Answer 21

Solve 5x2 = -30x - 65.

Answer 22

@DanJS ?

Answer 23

@wio can you help?