Question

Solve for X.

(2x+5)(6x-1)=120

Answer 1

(2x + 5)(6x - 1) = 120

12x^2 - 2x + 30x - 5 = 120

12x^2 + 28x - 125 = 0

x = [-28 +/- sqrt(784 + 4*12*125)]/24

x = [-28 +/- sqrt(6784)]/24

x = [-28 +/- 8sqrt(106)]/24

x = [-7 +/- 2sqrt(106)]/6

Though they are ugly, these are your two solutions to the original equation.

Answer 2

can u do it take a pic of it and attach it so i see what it is meaning i dont understand this

Answer 3

no because im on my computer so, go on google and search tiger algebra and plug it in on there it should give you a better explanation

Answer 4

this makes no sense

Answer 5

Andrew, do you know how to multiply the equation?
(2x+5)(6x-1)=120

Answer 6

no its been too long

Answer 7

That would be the first step.
Taylor0402 already multiplied it for you and it is
12x^2 - 2x + 30x - 5 = 120

Answer 8

Andrew if it has been a long time since you have done algebra, are you even ready to be doing this type of math?

Answer 9

i am doin this to help my gf. My memory loss is whats making it harder to remember its been 3 years since i did this that i can remember and am wanting to learn it again so i can help her with her homework and get better at this again. i had straight a's when i had done it but yeah.

Answer 10

Okay, the next step is to get the equation
12x^2 - 2x + 30x - 5 = 120
and add the terms so you can have an equation with just 3 terms.
Can you do that?

Answer 11

other subjects from this i know still because i use it everyday

Answer 12

Can you do what I asked you in the posting above?

Answer 13

12x^2-2x+30x-125=0?

Answer 14

Okay but you have to combine the -2x with +30x

Answer 15

oh yeah
12x^2+28-125=0

Answer 16

Now you solve the equation using the Quadratic Formula

Answer 17

The "a" term is 12
The "b" term is 28
The "c" term is -125

Answer 18

\[\frac{ -28+/-\sqrt{28^2-4(12x-125)} }{ 2a }\]

Answer 19

yes?

Answer 20

That should be 28^2 -4*12*-125
and 2a should be 2* 12 or 24

Answer 21

use equation button on here please so i can understand

Answer 22

\[4 a c = 4*12*-125\]

Answer 23

It is NOT 4 *(12 -125)

Answer 24

ok

Answer 25

and 2a = 2 * 12 or 24

Answer 26

can u make the whole thing i did with the fixes so i see how it should be?

Answer 27

\[x = (-28 ± \sqrt{28² - 4*12*-125} ) ÷ 2*12\]

Answer 28

\[x = (-28 ±\sqrt{784 +6,000} ) ÷ 24\]

Answer 29

ok

Answer 30

Okay then

Answer 31

what next

Answer 32

\[x = (-28 ±\sqrt{6,784} ) ÷ 24\]

Answer 33

Taylor 0402 pretty much did what I just did so look for that solution almost at the top of this posting.

Answer 34

thanks

Answer 35

now i understand