Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

**brittany1595****Member**- Registered: 2013-10-01
- Posts: 7

slant height= 10 Base= 6

This triangle just became the base of a regular prism, with a height of 8:

12. What is the lateral area?

A= 128

13. What is the volume?

V= 96

14. What is the area of the largest rectangular side?

I have a rectangle, with a length of 7 and a width of 4:

15. What is the perimeter?

16. What is the area?

*Last edited by brittany1595 (2013-10-01 05:19:05)*

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 106,389

15. What is the perimeter?

P = 2L + 2W

P = 2(7) + 2(4) = 22

16. What is the area?

A = L x W

A = 7 x 4 = 28

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.****No great discovery was ever made without a bold guess. **

Offline

**brittany1595****Member**- Registered: 2013-10-01
- Posts: 7

thank you! what about 14?

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 106,389

Does your prism look like this?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.****No great discovery was ever made without a bold guess. **

Offline

**brittany1595****Member**- Registered: 2013-10-01
- Posts: 7

yes

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 106,389

14)

This is the slant height.

Then the area of the largest side is 10 x 8 = 80

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.****No great discovery was ever made without a bold guess. **

Offline

**bob bundy****Moderator**- Registered: 2010-06-20
- Posts: 7,706

hi brittany1595

Welcome to the forum.

I've only just got in after being out all day. Hope it's not too late to help you with these.

slant height= 10 Base= 6

This triangle just became the base of a regular prism, with a height of 8:I've made a picture below to show what I think this is like. It's easier for me to show the prism on its side so that the triangular base becomes the front, and the height becomes the depth going backwards.

These questions sound like they're from Compu High, in which case I hope that's what they mean by the slant height.

12. What is the lateral area?

A= 128

The side rectangles are 10 by 8, 10 by 8 and 6 by 8. That doesn't come to 128.

13. What is the volume?

V= 96

To get the volume, you need the area of the triangular end and then multiply by 8.

So you'll have to use Pythagoras' theorem to calculate the height of the triangle (dotted in my diagram), then do half base times height, the times by 8.

That won't make 96.

14. What is the area of the largest rectangular side?You've got that as part of Q12.

I have a rectangle, with a length of 7 and a width of 4:

15. What is the perimeter?

The perimeter is the distance around the outside so calculate 7 + 4 + 7 + 4.

16. What is the area?

length times width.

Hope that helps. Let us know how you get on with these.

Bob

Children are not defined by school ...........The Fonz

You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei

Offline