A community for students.
Here's the question you clicked on:
 0 viewing
 2 years ago
If the equation x^2+(7+a)x+7a+1=0 has equal roots,find the value of a.
.
.
.
ANSWER = {9,5}
 2 years ago
If the equation x^2+(7+a)x+7a+1=0 has equal roots,find the value of a. . . . ANSWER = {9,5}

This Question is Closed

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2For a root with multiplicity two you need to need to have the discriminant equal to 0.

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2So what I'm saying is: \[Ax^2+Bx+C=0 => \text{ discriminant } = B^24AC\] And we want here for the discriminant=0

koli123able
 2 years ago
Best ResponseYou've already chosen the best response.0but what is b and a and c the equation is a bit confusing

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2Since we want root with multiplicity 2 :) So \[B^24AC=0\]

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2\[\text{ you have } x^2+(7+a)x+(7a+1)=0\]

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2A is the number in front of x^2 B is the number in front of x C is the leftover part

koli123able
 2 years ago
Best ResponseYou've already chosen the best response.0\[x^2+(7+a)x+7a+1=0\]

koli123able
 2 years ago
Best ResponseYou've already chosen the best response.0A=1 B=(7+a) c=(7a+1)

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2\[(7+a)^24(1)(7a+1)=0\]

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2That is B^24AC=0 You think you can solve that reply above for a?

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2I think you mean 28a since 4(7)=28 not 14

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2well .... I think your 53 is a little off. you have 494 you forgot to distribute that  earlier

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2\[49+14a+a^24(7a+1)=0\] \[49+14a+a^228a4=0\] Now try combining like terms.

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2yep do you know how to factor?

koli123able
 2 years ago
Best ResponseYou've already chosen the best response.0yep but i am solving this with quadratic is it ok?

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2The quadratic formula? That is fine. :)

Miyuru
 2 years ago
Best ResponseYou've already chosen the best response.0I solved it by factors..

Miyuru
 2 years ago
Best ResponseYou've already chosen the best response.0thnx @myininaya U are great. Nice help

koli123able
 2 years ago
Best ResponseYou've already chosen the best response.0got 2 values 9 and 5 of a

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2Great! You go guys! :)

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2If you guys didn't understand why I set the discriminant equal to 0, then I will try to explain as best as possible. If discriminant is equal to 0, then you will have on root (multiplicity 2) If discriminant is equal to negative number, you have two imaginary solutions If discriminant is equal to positive number, you have two real solutions.

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2The discriminant is \[B^24AC \]

Miyuru
 2 years ago
Best ResponseYou've already chosen the best response.0@myininaya how to solve the equation to get the discriminant..

myininaya
 2 years ago
Best ResponseYou've already chosen the best response.2\[x=\frac{b \pm \sqrt{b^24ac}}{2a} \text{ is called the quadratic formual } \] The discriminant is that thing under the radical It is what determines if you have one root (w/ multiplicity 2) , imaginary roots, or real roots.

Miyuru
 2 years ago
Best ResponseYou've already chosen the best response.0So to slove the equation should i find a b c
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.