Question

the base of a prism is an equlateral triangle of perimetre 21 centimetres and its height 6 cm what is its total surface area​

Answer 1

Step-by-step explanation:

the base of a prism is an equlateral triangle of perimetre 21 centimetres and its height 6 cm what is its total surface area

Answer 2

Answer:

Given: the base is a right angled triangle with sides a=6cm, b=8cm, c=10cm and T.S.A=156cm

2

. We know that

T.S.A.=2B+Ph=2×

2

1

×8×6+(6+8+10)h=48+24h.

Thus 48+24h=156. This implies that 24h=156−48=108.

Hence h=

24

108

=4.5cm.

Therefore LSA=Ph=(6+8+10)×4.5=24×4.5=108cm

2

.