Question

Solving quadratic Equations by factoring:
8x^2+2x=3

Answer 1

do you have to use quadratic formula or any method?

Answer 2

Quadratic Formula

Answer 3

What??

Answer 4

\[\frac{ x = -(b) ± \sqrt b^2 - 4(a)(c)}{ 2(a)}\]

Answer 5

We want to get a C value too so subtract 3 from both sides and you get
\[8x^2+2x-3=0\]

Answer 6

So:
A=8
B=2
C=-3

Answer 7

Then you factor it out right?

Answer 8

yep

Answer 9

and you get (4x-1)(2x-3)

Answer 10

I think

Answer 11

And for your zeros you get 1/4 and -6/2 I think?

Answer 12

lets do it step by step
\[\frac{ x=−(2)±√2^2−4(8)(-3) }{ 2(8) }\]
now when you do this you get...
\[\frac{ -2 ±\sqrt{100}}{ 16 }\]

Answer 13

Whoa.. I have never done it like that. Im only in algebra one?

Answer 14

so am i :) this is an easier way

Answer 15

Oh okay

Answer 16

Do you get it uptil this part?

Answer 17

Yes your just simplifying, right?

Answer 18

Now all you do is split the equation :)
\[\frac{ -2+\sqrt{100} }{ 16 }\]
and
\[\frac{ -2-\sqrt{100} }{ 16 }\]

Answer 19

And you get your zeros,
So you get 1/2 and -3/4????

Answer 20

1)-3/4
2)1/2
yep :)

Answer 21

Wow thanks! Can I do a few more with you?

Answer 22

is factoring and using quadratic formula same

Answer 23

Just to make sure I get it?

Answer 24

Yeah but i need to make sure i've done this right :) @mathmath333 @perl is it correct?

Answer 25

Okay well I'll put the equation in:
So the equation is 3x^2-x=4

Answer 26

Can you make another post for it please

Answer 27

looks like answer is correct

Answer 28

Yay!!! :D

Answer 29

https://www.mathsisfun.com/algebra/factoring-quadratics.html

Answer 30

Oh you wanted it by factoring :/ i dont know that way i only know this way

Answer 31

Whats this way?

Answer 32

\(\large \color{black}{\begin{align} &8x^2+2x=3\hspace{.33em}\\~\\
&\implies 8x^2+2x-3=0\hspace{.33em}\\~\\
&\implies \color{red}{8}x^2+\color{blue}{6}x-\color{blue}{4}x-\color{red}{3}=0\hspace{.33em}\\~\\
&\implies 2x(4x+3)-(4x+3)=0\hspace{.33em}\\~\\
&\implies (2x-1)(4x+3)=0\hspace{.33em}\\~\\
\end{align}}\)

note that

\(\large \color{black}{\begin{align}
\color{red}{8\times 3}=\color{blue}{6\times 4}
\end{align}}\)

Answer 33

this way was simplifying (the one i did)

Answer 34

u have to write \(2x\) (here \(6x-4x\)) such that it equals \(=8\times 3=24\)
and \(6\times 4=24\)

Answer 35

Oh does it still give the same answer I get when factoring and thank you @mathmath333

Answer 36

yes it gives same answer solve further and check

\(\large \color{black}{\begin{align} \
&\implies (2x-1)(4x+3)=0\hspace{.33em}\\~\\
\end{align}}\)

Answer 37

1/2 and -3/4??

Answer 38

yes

Answer 39

Awesome! Thanks!