# Math 11

• Feb 29th 2012, 01:20 PM
Montelneedshelp
Math 11
The roof of a building is shaped like a square pyramid, with a base of 18m by 18m. If the slant height of the roof is 12m and roofing costs 5.75m2, how much will it cost for roofing material?

thanks if you helped.(Bow)
• Feb 29th 2012, 05:21 PM
skeeter
Re: Math 11
Quote:

Originally Posted by Montelneedshelp
The roof of a building is shaped like a square pyramid, with a base of 18m by 18m. If the slant height of the roof is 12m and roofing costs 5.75m2, how much will it cost for roofing material?

thanks if you helped.(Bow)

hint: triangle area = (1/2)bh
• Mar 1st 2012, 01:43 AM
princeps
Re: Math 11
Quote:

Originally Posted by Montelneedshelp
The roof of a building is shaped like a square pyramid, with a base of 18m by 18m. If the slant height of the roof is 12m and roofing costs 5.75m2, how much will it cost for roofing material?

thanks if you helped.(Bow)

Area of the roof = $\displaystyle A=4\cdot \frac{18 \cdot 12}{2}$

Cost of the roof = $\displaystyle C=5.75 \cdot A$
• Mar 2nd 2012, 05:03 PM
Wilmer
Re: Math 11
Did you do some work, like googling "square pyramid" ?