Question

Q5. The edges of a triangular board are 5 cm, 12 cm and 13 cm. Find the cost of painting it at the rate of Rs 9 per cm2.​

Answer 1

Answer:

270

Step-by-step explanation:

a=5 cm

b=12 cm

c=13 cm

s=a+b+c/2

=5+12+13/2

=30/2

=15

area of Δ=√s(s-a)(s-b)(s-c)

=√15(15-5)(15-12)(15-13)

=√15*10*3*2

=√3*5*2*5*3*2

=√900

=30 cm²

cost of painting it=30*9

=270 rupees