A community for students.
Here's the question you clicked on:
 0 viewing
AshhSmith
 3 years ago
a^2 – a – 20 factor completely
AshhSmith
 3 years ago
a^2 – a – 20 factor completely

This Question is Closed

vishweshshrimali5
 3 years ago
Best ResponseYou've already chosen the best response.0\[a^2  a  20 = a^2  5a + 4a  20\] Now u can simplify this

agentx5
 3 years ago
Best ResponseYou've already chosen the best response.1Hint: 5 and +4 ;) Got it now?

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.4From @vishweshshrimali5 's work: a^2  a  20 = a^2  5a + 4a  20 = a (a5) + 4(a5) = (a+4)(a5) If you have to solve the quad. equation, that's another case.

agentx5
 3 years ago
Best ResponseYou've already chosen the best response.1a^2a20=(a5)(a+4) I stand by what I said. 5 + 4 = 1 5 * 4 = 20

agentx5
 3 years ago
Best ResponseYou've already chosen the best response.1So no, not wrong answer. Dude.

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.4Sorry @vishweshshrimali5 I think you're more like solving the quadratic equation than just factor the expression. Please look at the question again

vishweshshrimali5
 3 years ago
Best ResponseYou've already chosen the best response.0@Callisto very correct I regret for my mistake We just had to factorise right ?

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.4Root is negative of the number in the factor. I'm 100% sure that @agentx5 is correct!

agentx5
 3 years ago
Best ResponseYou've already chosen the best response.1I'm not using the quadratic. I'm doing it in my head by considering what would have to come back together to for a^2a20 when I F.O.I.L. the factors together.

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.4Yes @vishweshshrimali5

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.4@vishweshshrimali5 You shouldn't be sorry. Instead we are so sorry to tell you that the question is *factor completely*

agentx5
 3 years ago
Best ResponseYou've already chosen the best response.1Neither Callisto nor I have forgotten, this is just a method that works easier and faster in this situation as a method to factor, and just as correct. Roots implies an EQUATION, not an EXPRESSION.

agentx5
 3 years ago
Best ResponseYou've already chosen the best response.1There is no '=' in the original question.

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.4@vishweshshrimali5 No. If it is the quadratic equation. It is solve like this: a^2 – a – 20 =0 (a5)(a+4) =0 a5 =0 or a+4 =0 a=5 or a=4

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.4@vishweshshrimali5 I've posted the way to do it

AshhSmith
 3 years ago
Best ResponseYou've already chosen the best response.0can you factor a^2 – 5a – 20 out for me ?

vishweshshrimali5
 3 years ago
Best ResponseYou've already chosen the best response.0@Callisto I think I have misunderstood u all Sorry for that

vishweshshrimali5
 3 years ago
Best ResponseYou've already chosen the best response.0What @agentx5 was saying were not roots right ? u were telling how to write x = 5x + 4x right ? Sorry everyone I regret for my words

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.4It's okay. Is that clear to you now? @vishweshshrimali5

agentx5
 3 years ago
Best ResponseYou've already chosen the best response.1But then again there was NO f(a)=0 equation, it was simply an expression. @AshhSmith , Callisto and I both did that (see above) :)

vishweshshrimali5
 3 years ago
Best ResponseYou've already chosen the best response.0If I m not wrong @Callisto told the way to factorise @agentx5 told how to write x = 5x + 4x and I told how to solve the quadratic eq. Sorry everyone Please don't mind that

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.4@AshhSmith First, please post it as a new question. Second, I'm sure we're all glad to help, provided that you've tried to work out the answer first  no matter you succeed or not. Third, in response to your question, if you need to form (ax+b)(cx+d) where a, b, c, and d are integers, then it can't be factored in the case x^25x20.

Callisto
 3 years ago
Best ResponseYou've already chosen the best response.4@vishweshshrimali5 I hope I can explain it clearly to you... First it's about 'factor completely' Factor completely is about factoring the expression. The expression given in the question is x^2 x  20 So, we have to factor it. x^2  x 20 = x^2  5x + 4x  20 = x (x5) + 4(x5) = (x5)(x+4) This is what factor completely is, and nothing more. What you've been talking about is solve the equation. And the way you've been working is to use some properties of quadratic equation to work out the roots ( that is the value of the unknowns) of the quadratic equation. With the word ''equation'', that means there are TWO sides and a equal sign in between (that is '=') and you need to SOLVE it. For example : x^2 x  20 = 0 > you can see there are TWO sides separated by an equal sign. To solve it. One of the techniques is to factor it. That is x^2 x  20 = 0 (x5)(x+4) = 0 Since two factors multiply to give 0, one of them must be 0. So, (x5) =0 or (x+4) =0 x = 5 or x = 4 This is solving the equation/ solve x/ find the roots of the equation, but NOT factor the expression. I hope it's clearer to you now.
Ask your own question
Sign UpFind 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.