A community for students.
Here's the question you clicked on:
 0 viewing
Ledah
 4 years ago
Two regular decagons have areas of 30 mm² and x² + 7x mm². What values of x make the decagons congruent?
Ledah
 4 years ago
Two regular decagons have areas of 30 mm² and x² + 7x mm². What values of x make the decagons congruent?

This Question is Closed

apoorvk
 4 years ago
Best ResponseYou've already chosen the best response.1Since the areas are equal, equate the expressions for both areas: \[30 = x^2 + 7x\] Now, bring every term to the same side, and lo! you have a quadratic. solve it, find 'x' and enjoy!

FoolAroundMath
 4 years ago
Best ResponseYou've already chosen the best response.1Two polygons are congruent if they are exactly the same. What can you say about the area of two congruent polygons?

Ledah
 4 years ago
Best ResponseYou've already chosen the best response.0They should also be the same

FoolAroundMath
 4 years ago
Best ResponseYou've already chosen the best response.1So, all you have to do is equate their areas and get a quadratic equation as obtained by @apoorvk and solve it.

Ledah
 4 years ago
Best ResponseYou've already chosen the best response.0I got 5 and 6 as an answer.. I'm not sure if its right I'm still checking my work

apoorvk
 4 years ago
Best ResponseYou've already chosen the best response.1Umm, sorry that isn't correct  did you split the middle term and factorize it?

FoolAroundMath
 4 years ago
Best ResponseYou've already chosen the best response.1\(x=5\) does not satisfy the equation. What you have is \(x^{2}+7x30 = 0\) Can you factorise the left hand side?
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.