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 2 years ago
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
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

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Sunshine447
 2 years ago
Best ResponseYou've already chosen the best response.1please 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!

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

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

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

Yahoo!
 2 years ago
Best ResponseYou've already chosen the best response.3Sum = 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

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

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

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

ParthKohli
 2 years ago
Best 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?

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

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

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

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

ParthKohli
 2 years ago
Best ResponseYou've already chosen the best response.0Hmm, 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.

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

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

ParthKohli
 2 years ago
Best ResponseYou've already chosen the best response.0Okay, 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?

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

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

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

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

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

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

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