A carpenter is building a roof on a barn that is w feet wide and l feet long. The roof will be covered by corrugated tin and the carpenter needs to know the area of the roof to estimate the amount of tin to purchase. The roof will have a pitch of 4:12. Find an expression for the area of the roof in terms of w and l.

Question

A carpenter is building a roof on a barn that is w feet wide and l feet long.  The roof will be covered by corrugated tin and the carpenter needs to know the area of the roof to estimate the amount of tin to purchase.  The roof will have a pitch of 4:12.  Find an expression for the area of the roof in terms of w and l.

blurryface · Answer

Hello @Sachintha

sachintha · Answer

Hi! :)
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Can you fill the sides with the respective values?

blurryface · Answer

@Sachintha

sachintha · Answer

Is my drawing ok?

blurryface · Answer

I already have that exact drawing...

sachintha · Answer

But it's without the dimensions. 
It has a pitch of 1:3. Which mean a drop of 1 for every 3 in width. So what will be the width of the roof?

blurryface · Answer

they don't give us the length or the width, that's what we solve for.

sachintha · Answer

Nope. They have already given us the length and width of the barn and roof pitch. Length of the roof is the same as that of the barn, but the width differs. That's what we are going to find.

sachintha · Answer

Now you can find the area of the roof since we have width and the length of the roof. :)

blurryface · Answer

how?

blurryface · Answer

@nincompoop

blurryface · Answer

http://openstudy.com/updates/50a6a44fe4b082f0b852bbb4 why 2 different answers

sachintha · Answer

I am sorry. I took the width of half of the roof as w. It should be w/2. Hope you could understand it from that question. :)

blurryface · Answer

I'm totally lost

sachintha · Answer

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