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Sunshine447
Group Title
Solve the equation by factoring:
x2  7x + 12 = 0
A)
x = 3 or 4
B)
x = 3 or 4
C)
x = 3 or 4
D)
x = 3 or 4
 2 years ago
 2 years ago
Sunshine447 Group Title
Solve the equation by factoring: x2  7x + 12 = 0 A) x = 3 or 4 B) x = 3 or 4 C) x = 3 or 4 D) x = 3 or 4
 2 years ago
 2 years ago

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Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
please don't just give me the answer.... I want to actually try to learn how to do it. Also, know how to do this the "plug and play" method, but I need to know how to do it when it's not multiple choice. Thanks!
 2 years ago

jiteshmeghwal9 Group TitleBest ResponseYou've already chosen the best response.1
sorry dude
 2 years ago

jiteshmeghwal9 Group TitleBest ResponseYou've already chosen the best response.1
first factorize the L.H.S. & then gt ur answer
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Hi, Sunshine! Would you like to know the whole process from the start?
 2 years ago

Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
yes please! Thanks Spiderman! haha
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.3
Sum = 7 Product = 12 two numbers 4 and 3 x^2 4x  3x + 12 =0 x(x4) 3(x4) (x4) (x3) x = 3 or x = 4
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
All right then. Do you know what the standard form of a quadratic equation is?
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.3
@Sunshine447 Did u understand!
 2 years ago

Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
@ParthKohli yes
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Okay, what is it?
 2 years ago

Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
ax + bx + c = 0 right?
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
\(ax^2 + bx + c = 0\)* What you first do is find the product of \(a\) and \(c\). What are \(a\) and \(c\) here?
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.3
@Sunshine447 Did u understand my method????
 2 years ago

Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
a=1 and c=12
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Right! What's the product of 1, 12?
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Correct! :) Now you have to find two numbers that add to get \(b\) and multiply to get the product of \(a\) and \(c\).
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Do you know two numbers such that: Their sum is 7. Their product is 12. ?
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Hmm, you may find them by trial and error. Note that a negative number times a negative number is a positive number, so those numbers must be negative if the sum of negative.
 2 years ago

Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
3 and 4
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
You got it! Now, we will 'split' the middle term with these coefficients. \(7x = 3x  4x \Longrightarrow x^2  7x + 12 = x^2  3x  4x + 12\)
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Do you get it till this point?
 2 years ago

Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
yeah i think so
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Okay, now we basically factor by 'grouping'. What you must do is factor the first two and last two terms. \(x^2  3x = x(x  3)\) \(4x + 12 = 4(x  3)\) Get it till here?
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
So, \(x^2  3x  4x + 12 = x(x  3)  4(x  3)\). \(x(x  3)  4(x  3) \Longrightarrow ( x  4)( x  3)\)
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Are you there? Do you get it?
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Okay, so \((x  4)(x  3) = 0\). Do you know the 'zeroproduct rule'?
 2 years ago

Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
i dont think so
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
All right, you have two solutions here. \( \color{Black}{\Rightarrow x  4 = 0}\) \( \color{Black}{\Rightarrow x  3 = 0}\)
 2 years ago

Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
okay...
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
Can you solve those equations? That is how you get the solutions.
 2 years ago

Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
x=4 and 3
 2 years ago

Sunshine447 Group TitleBest ResponseYou've already chosen the best response.1
Thanks!
 2 years ago

ParthKohli Group TitleBest ResponseYou've already chosen the best response.0
You're welcome!
 2 years ago

TheViper Group TitleBest ResponseYou've already chosen the best response.0
\[\LARGE{x^27x+12=0}\]\[\Large{x^23x4x+12=0}\]\[\Large{x(x3)4(x3)=0}\]\[\Large{(x3)(x4)}\]\[\Large{\color{green}{x=3\space or \space4}}\]
 2 years ago

TheViper Group TitleBest ResponseYou've already chosen the best response.0
So A. is the right answer ;)
 2 years ago

TheViper Group TitleBest ResponseYou've already chosen the best response.0
Understood ???
 2 years ago
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