Hey there! Sign in to join this conversationNew here? Join for free
x Turn on thread page Beta
    • Thread Starter
    Online

    6
    ReputationRep:
    they give me three co-ordinates of a triangle and tell me to work out the area but you don't know the height of the triangle since the base doesn't make a straight line
    Offline

    1
    ReputationRep:
    Work out the length of each of the sides using Pythagoras, then use the cosine rule to work out one of the angles
    then use the formula area= 1/2 a b sin(c)
    Offline

    1
    ReputationRep:
    (Original post by DedeM9)
    they give me three co-ordinates of a triangle and tell me to work out the area but you don't know the height of the triangle since the base doesn't make a straight line
    Give me the picture of the question since you're not being specific with the details here... -.-
    Offline

    1
    ReputationRep:
    (Original post by Radical Lemon)
    Work out the length of each of the sides using Pythagoras, then use the cosine rule to work out one of the angles
    then use the formula area= 1/2 a b sin(c)
    You don't need to know that for C1??
    Online

    21
    ReputationRep:
    (Original post by Radical Lemon)
    Work out the length of each of the sides using Pythagoras, then use the cosine rule to work out one of the angles
    then use the formula area= 1/2 a b sin(c)
    Im pretty sure if it's C1 it'll be the basic 1/2*base*height?
    Offline

    20
    ReputationRep:
    (Original post by zayn008)
    Im pretty sure if it's C1 it'll be the basic 1/2*base*height?
    Yup I think in C1 there's always a perpendicular angle.
    Online

    21
    ReputationRep:
    AH! You use the mid point of the base and the top co-ordinate to work out the height!!!!!
    Online

    21
    ReputationRep:
    (Original post by XOR_)
    Yup I think in C1 there's always a perpendicular angle.
    Yeah usually they build it up, so I bet before this question they asked to show 2 lines are perpendicular, that or you can use the base mid points and the top co-ordinate to get the length of the height
    Offline

    17
    ReputationRep:
    (Original post by zayn008)
    Im pretty sure if it's C1 it'll be the basic 1/2*base*height?
    I believe this is correct.
    Remember it is base times PERPENDICULAR (vertical) height, not the slanted height.
    (Original post by Zacken)
    It's usually referred to as the perpendicular height.
    Offline

    17
    ReputationRep:
    (Original post by zayn008)
    AH! You use the mid point of the base and the top co-ordinate to work out the height!!!!!
    Do you have an example questions?
    Offline

    1
    ReputationRep:
    (Original post by Someboady)
    I believe this is correct.
    Remember it is base times VERTICAL height, not the slanted height.
    Doing past papers... and those are the only questions I've found.
    Online

    22
    ReputationRep:
    (Original post by Someboady)
    I believe this is correct.
    Remember it is base times VERTICAL height, not the slanted height.
    It's usually referred to as the perpendicular height.
    Offline

    17
    ReputationRep:
    (Original post by Zacken)
    It's usually referred to as the perpendicular height.
    Sorry...still a bit of a maths noob I'll quote you in.
    Online

    22
    ReputationRep:
    (Original post by Someboady)
    Sorry...still a bit of a maths noob I'll quote you in.
    You weren't wrong at all, nothing nooby about it. Was just a quick tip.
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: May 15, 2016
Poll
Do I go to The Streets tomorrow night?
Useful resources

Make your revision easier

Maths

Maths Forum posting guidelines

Not sure where to post? Read the updated guidelines here

Equations

How to use LaTex

Writing equations the easy way

Student revising

Study habits of A* students

Top tips from students who have already aced their exams

Study Planner

Create your own Study Planner

Never miss a deadline again

Polling station sign

Thinking about a maths degree?

Chat with other maths applicants

Can you help? Study help unanswered threads

Groups associated with this forum:

View associated groups

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.