Question

1 2 2 2
18. If 3A = 2 1 -2 then show that A-' = AT.
-2 2-1​

Answer 1

Step-by-step explanation:

Given:

Perimeter=250m

⇒Area of 4 walls =2lh+2bh

=2(b+l)h

⇒Perimeter of floor of wall =2l+2b

⇒2(l+b)=250 m

∴ Area of 4 walls =2(l+b)h

=250h m

2

⇒Cost of painting per m

2

area = Rs. 10

⇒Cost of painting 250h m

2

area = Rs(250h×10)

= Rs.2500h

⇒Painting cost of walls = Rs. 15000

⇒2500h=15000

⇒h=

2500

15000

⇒h=6m