Please show work A room in the shape of a triangle has sides

Please show work

A room in the shape of a triangle has sides of length 15.0yd, 15.2 yd, and 13.9 yd. If carpeting cost $20.04 a sq yd and padding costs $ 2.10 a sq yd and there is no charge for installation, how much to the nearest dollar will it cost to carpet the room?

Solution

seipermeter , s = (15+15.2+13.9)/2 = 22.05 yd

area = sqrt(22.05 x 7.05 x 6.85 x 8.15) = 93.1586 sq yd

carpeting cost = 93.1586 x 20.04 = $1866.898

padding cost = 93.1586 x 2.1 = $195.633

total cost = 1866.898 + 195.633 = $ 2062.531