Question

Find the volume of a triangular prism with a height of 5 cm and a base that is a regular triangle with sides of 3 cm.

Answer 1

For all regular prism (a regular prism is one where the cross section is the same all along the length) the volume is always the cross sectional area multiply by the length.

So what is the shape of the cross section of this prism?

Answer 2

I suppose it would be a triangle

Answer 3

OK, what is the area of the triangle?

Answer 4

Note the term regular triangle means isosceles triangle. So how to determine the length of the base of the triangle?

Answer 5

Can you find the base?

Answer 6

no, the height is there but the base is incomplete.

Answer 7

You have a right angle triangle and you are given one side and one other angle. You should be able to find out the other side by using sin, cos or tan.

Answer 8

So well need Tan correct?

Answer 9

Note: The reason why the angle is 60 degree is because the triangle is isosceles.

Answer 10

yes. Work that out and let me know what is the base