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The perimeter of a building is 78 feet. The width of the building is seven more than three times the length of the building. What is the width of the building? Solve algebraically Justify your answer using math vocabulary. MUST USE COMPLETE SENTENCES​

1 Answer

3 votes

P=2l+2w

W=7+3l

So substitute into the original equation

P=2l + 2(7+3l)

78=2l +14 + 6l

-14 -14

—————-

64=8l

8=length

W=7+3l

= 7+3(8)

=7+24

=31

Check your work

Perimeter=8+8+31+31

=78

Hope this helps

User Michael Platings
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