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Help me Please

 

World Problems

 

Find the length and width.

 

The perimeter of a floor is 40 feet and its area 96 square feet.

 Mar 8, 2018
 #1
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0

Perimeter =2[L + W]

Area =L x W


2[L + W] = 40
L x W =96, solve for L, W

 

L=12  and  W = 8 - feet, or:

W = 12  and  L = 8 - feet.

 Mar 8, 2018
 #2
avatar+128089 
+1

Remember, Manuel.....

 

Perimeter  =  2W + 2L        and Area   = LW

 

So  

 

40  =  2W + 2L         divide through by 2

20  = W + L     subtract W  from both sides

20 - W  = L         (1)  

 

And

 

96  = LW       sub in (1)   for    L.....and we have

 

96  = (20 - W) * W       simplify

 

96 = 20W  - W^2       add W^2 to both sides, subtract 20W from both sides

 

W^2 - 20W  +  96  = 0        factor.....-8 and  - 12  are what we need

 

(W  - 8) ( W - 12)   = 0

 

Set each factor to 0  and solve for W

 

W  = 8    or   W  = 12

 

So, Manuel....we can let  W  = 8....so

 

 L = 20 - 8  = 12

 

So....Width  = 8   and Length   = 12

 

 

Check  - perimeter =  2W  + 2L  =   2(8)  + 2(12)   =  16 + 24  = 40

area  = 8 * !2   =  96     

 

Hope that helped......!!!!

 

 

cool cool cool

 Mar 8, 2018
 #3
avatar+1494 
+1

Yes sir it does

 

Thank you sir

 Mar 8, 2018

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