Raven W.

asked • 04/09/15

The area of a square table, is numerically equal to triple its perimeter find the length of a side of a square and then Find the area of the square

Using GCF

1 Expert Answer

By:

Sahil P. answered • 04/09/15

Tutor
New to Wyzant

Knowledgeable and Effective Tutor with Advanced Engineering Degree

See tutors like this
See tutors like this
Create some equations from the wording!
 
A (area) = 3 * P (perimeter)
 
For a square:
A = s * s (where "s" is the length of a side)
P = 4 * s
 
Once you substitute, you will get an equation that can be solved for "s".  There are technically two answers mathematically, but you will see that only one of the answers makes sense in this problem.  
 
Let me know if you have any questions! Good luck!
Upvote • 0 Downvote
More
Report

Raven W.

So can I substitute any number for s since they didn't give me a number to start with? I'm still a little confused 
Report

04/09/15

Sahil P.

No, what I mean by substitute is that you can substitute the equations for Area and Perimeter of a square into the equation at the top.  You can then solve for s.  
 
Hope that helps!  If you're still having trouble, get as far as you can and then let me know what you have so far so I can explain it further if needed!  Good luck!
Report

04/09/15

Raven W.

A= 4*4=16
P=4*16=64
then 3*64=192 ?? Is this right 
Report

04/09/15

Sahil P.

No, but let me show you why that is incorrect first.  
 
If A = 4*4=16, then P cannot be 4*16 since you just used 4 as "s".  
 
What I am saying is, you don't have to guess any numbers for the length of a side of a square.  Use the equation A=s*s and the equation P=4*s in the first equation, A=3*P, which is from the wording of the question.  
 
So if you substitute these equations for area and perimeter into the first equation, you get s*s = 3*(4*s). 
 
You can take this equation and solve for s.  There will be 2 mathematical solutions like I said, but only one will make sense for the length.  
Report

04/09/15

Raven W.

Ohhh so you have 3*(4*s)  then it's going to be 12*3s than you divide by 3s on both sides and it's going to give you 4=s ?? I hope I'm getting closer..
Report

04/09/15

Sahil P.

Getting closer!  :)
 
3*(4*s) is not 12*3s.  Look at it as 3*(4s).  What is that going to be?  
Report

04/09/15

Raven W.

Would it be just 12s?
Report

04/09/15

Sahil P.

Yup. So what equation does that leave you with?
Report

04/09/15

Raven W.

I have no clue would it leave me with the area equation ?
Report

04/09/15

Sahil P.

So you are left with s*s = 12s.  You can now solve this equation by moving all variables to one side and factoring.  
Report

04/09/15

Raven W.

can you give me a hint on how to factor that... So now I have 12s*s*s
Report

04/09/15

Sahil P.

You can't just move the 12s to the other side with the s*s in that way.  You can subtract it to get: s*s - 12s = 0.
 
So factor out an "s" to get s(s-12) = 0.  Now solve and you have your answer!
Report

04/09/15

Raven W.

Is that s^2-12s=0.. If Im wrong I'm soo sorry i know we been on this problem for a while 
Report

04/09/15

Still looking for help? Get the right answer, fast.

Ask a question for free

Get a free answer to a quick problem.
Most questions answered within 4 hours.

OR

Find an Online Tutor Now

Choose an expert and meet online. No packages or subscriptions, pay only for the time you need.