A community for students. Sign up today!
Here's the question you clicked on:
 0 viewing
 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

This Question is Closed

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 ;)
Ask your own question
Ask a QuestionFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.