Q15 A room in the shape of a triangle has sides of length 7

Q15. A room in the shape of a triangle has sides of length 7 yd, 8 yd, and 12 yd. If carpeting costs $16.50 a square yard and padding costs $5.25 a square yard, how much to the nearest dollar will it cost to carpet the room, assuming that there is no waste?
   a. $585
   b. $565
   c. $572
   d. $444

Q20. A room in the shape of a triangle has sides of length 6 yd, 10 yd, and 15 yd. If carpeting costs $17.50 a square yard and padding costs $4.25 a square yard, how much to the nearest dollar will it cost to carpet the room, assuming that there is no waste?
   a. $352
   b. $438
   c. $423
   d. $428

Solution

15

Area = sqrt[s(s-a)(s-b)(s-c) where s = ( a+b+c)/2

s =(7 +8+12)/2 = 13.5 sqyd

Area =sqrt[13.5( 13.5 -7)(13.5-8)(13.5 - 12)]

= 26.9 sqyd

carpeting costs $16.50 a square yard and padding costs $5.25 a square yard

Cost to carpet a room = 26.9( $ 16.50 + $ 5.25)

= $ 585.075

= $ 585

Option a

20.

Area = sqrt[s(s-a)(s-b)(s-c) where s = ( a+b+c)/2

s =(6 +10+15)/2 = 15.5 sqyd

Area =sqrt[15.5( 15.5 -7)(15.5-8)(15.5 - 12)]

= 20.12 sqyd

carpeting costs $17.50 a square yard and padding costs $4.25 a square yard

Cost to carpet a room = 20.12( $ 17.50 + $ 4.25)

= $ 437.61

= $ 438

Option b