Question

PLEASE HELP I WILL GIVE MEDAL
Part B: Solve 4x2 -12x + 5 = 0 using an appropriate method. Show the steps of your work, and explain why you chose the method used. (4 points)

Answer 1

Have you learned factoring?

Answer 2

This is an example of factoring trinomials :)

Answer 3

can you please help

Answer 4

im stuck and need to be done within the hour

Answer 5

this one factors

Answer 6

ok

Answer 7

do you know how it factors?

Answer 8

ehh not really :(

Answer 9

me neither
i cheat

Answer 10

:( lol

Answer 11

factors as
\[(2x-1)(2x-5)=0\] would you like to know how i know it?

Answer 12

Or that...

Answer 13

yes please!

Answer 14

i will wait and let @pooja195 explain
maybe i will learn something

Answer 15

i have never figured out a way to factor other than to grind it til i find it

Answer 16

thanks :)
Ok well fist you want to multiply the a and c value what do you get?

Answer 17

this is algebra 1 incase you where wondering!

Answer 18

Whats
\[\huge 5 \times 4 \]

Answer 19

20...

Answer 20

good and our B value is -12 right?

Answer 21

yes sir

Answer 22

ok

Answer 23

Now ask yourself what multiplies into -20 BUT also adds up to -12?

Answer 24

You will have 2 numbers...

Answer 25

2 and 10?

Answer 26

multiplies into 20...

Answer 27

or 4 and 5

Answer 28

oh right multiplies into 20 but adds to -12
you are close with 10 and 2

Answer 29

you need a sign on both numbers...

Answer 30

-2 and -10?

Answer 31

or -2 and 10

Answer 32

yes! :)
Now...
\[\huge~(4x^2-2)+(10x+5)\]

Answer 33

Now find the GCF

Answer 34

for each...

Answer 35

After @pooja195 is done, I can summarize it all into one huge message of steps so it won't seem all over the place :)

Answer 36

-2 for the first and 5 for the second?

Answer 37

thank you aureyliant!

Answer 38

\(\huge~(4x^2-2\color{red}{x})+(10x+5)\)

Answer 39

Are you trying to find the zeros?

Answer 40

\(\huge~(4x^2-2\color{red}{x})\color{red}{-}(10x\color{red}{-}5)\)

Answer 41

You have the signs messed up but 2x and 5 is right :)
\[\huge 2x(2x-1)+5(2x-1)\]

Answer 42

*minus

Answer 43

xD

Answer 44

so 2x(2x-1) - 5 (2x-1)?

Answer 45

i know but im making sure that was correct XD

Answer 46

(2x - 5)(2x - 1)

Answer 47

now you just combine the parenthese and the outter numbers
(2x-5)(2x-1)
and you end up with Sat's grinding :P

Answer 48

You need to combine the first loner and the second loner and bring them together

Answer 49

ok is that all to it?

Answer 50

Then you set both equations to 0

Answer 51

Trying to factor by splitting the middle term

2.1 Factoring 4x2-12x+5

The first term is, 4x2 its coefficient is 4 .
The middle term is, -12x its coefficient is -12 .
The last term, "the constant", is +5

Step-1 : Multiply the coefficient of the first term by the constant 4 • 5 = 20

Step-2 : Find two factors of 20 whose sum equals the coefficient of the middle term, which is -12 .

-20 + -1 = -21
-10 + -2 = -12 That's it

Step-3 : Rewrite the polynomial splitting the middle term using the two factors found in step 2 above, -10 and -2
4x2 - 10x - 2x - 5

Step-4 : Add up the first 2 terms, pulling out like factors :
2x • (2x-5)
Add up the last 2 terms, pulling out common factors :
1 • (2x-5)
Step-5 : Add up the four terms of step 4 :
(2x-1) • (2x-5)
Which is the desired factorization

Equation at the end of step 2 :

(2x - 5) • (2x - 1) = 0
Step 3 :

Solve (2x-5)•(2x-1) = 0
(This goes towards solving for the zeros but that's only if the Q is asking that, too)

Answer 52

2x-5=0
2x-1=0

Answer 53

^^ Yup

Answer 54

ok

Answer 55

Solve it .-.

Answer 56

Now you could either do that or use the quadratic formula

Answer 57

But thats a story for another day

Answer 58

^no

Answer 59

Just set it to 0 its sooooo much more easier

Answer 60

Solving a Single Variable Equation :

3.2 Solve : 2x-5 = 0

Add 5 to both sides of the equation :
2x = 5
Divide both sides of the equation by 2:
x = 5/2 = 2.500
Solving a Single Variable Equation :

3.3 Solve : 2x-1 = 0

Add 1 to both sides of the equation :
2x = 1
Divide both sides of the equation by 2:
x = 1/2 = 0.500

Answer 61

can you guide me through setting through 0?

Answer 62

It depends on the type of factoring Q Pooja

Answer 63

2x-5=0
we want to isolate X

Answer 64

It may not be as easy to split the middle term

Answer 65

ok

Answer 66

so start by adding 5

Answer 67

that way on the left side the 5 will cancel what does the equation look like now?

Answer 68

ok so 2x=5?

Answer 69

Yes now just divde both sides by 2

Answer 70

what do you get?

Answer 71

1x=1/2????

Answer 72

No

Answer 73

keep the 5

Answer 74

Now we know the two values for x... also I summarized solving for the zeros above @cacaman

Answer 75

you get x=5/2

Answer 76

X=5?

Answer 77

just kidding

Answer 78

-_- i gave u the answer :P

Answer 79

2x-1=0
solve

Answer 80

I think you answered this one earlier...

Answer 81

2x=1

Answer 82

so 1/2

Answer 83

YES!
now what are the 2 answers?

Answer 84

please get this right -.-

Answer 85

5/2 and 1/2