A floral design on a floor is made up of 16 tiles which are triangular, the sides of the triangle being 9cm, 28cm and 35cm. Find the cost of
polishing the tiles at the rate of 50p per m^2?

Answer

Area of tiles = 16 x area of 1 Δ

S=  

2

a+b+c

=  

2

9+28+35

=  

2

72

=36

Area=  

36(36−9)(36−28)(36−35)

36×27×8×1

36  

6

cm  

2

Area of tiles = 16 ×36  

6

=1410.20.

Cost of polishing per cm  

2

 = 50.

Cost of polishing = 1410.90 cm  

2

1410.90 x  

2

1

705.45

Step-by-step explanation:

check the picture below.

arithmetic sequence

step-by-step explanation:

given that a sequence has terms as

19, 15, 11,

this is represented on a graph

the pattern indicates that the sequence is an arithmetic sequence with i term

a=19 and common difference d =-4

any general term

thus the sequence is reduced by 4 for each successive term starting from 1 and nth term is

24-5n.

first negative term would start after 5th term

5th term =24-25< 0

from 5th term onwards the sequence would be negative.