Hey there! Sign in to join this conversationNew here? Join for free

Simultaneous equations Watch

Announcements
    • Thread Starter
    Offline

    16
    ReputationRep:
    Solve the following simultaneous equations:

    Name:  1455233751362-1278823070.jpg
Views: 73
Size:  516.0 KB
    Offline

    2
    ReputationRep:
    Hi, you're factorising is wrong just after the line "ac =" (what exactly does this mean btw?)

    Name:  image.jpg
Views: 46
Size:  420.4 KB
    • TSR Support Team
    • Study Helper
    Offline

    20
    ReputationRep:
    (Original post by IFoundWonderland)
    Solve the following simultaneous equations:

    Name:  1455233751362-1278823070.jpg
Views: 73
Size:  516.0 KB
    ii.

    You have factorised -3y^2-3y to get -3y(y+3). This is incorrect - have another go.

    Your method will work but I would have taken out a factor of 3 from the quadratic (and moved everything to the other side) to make it simpler.
    • TSR Support Team
    • Study Helper
    Offline

    20
    ReputationRep:
    (Original post by JohnnyDavidson)
    Hi, you're factorising is wrong just after the line "ac =" (what exactly does this mean btw?)

    Name:  image.jpg
Views: 46
Size:  420.4 KB
    This is the 'ac' method of factorising quadratics.

    'a' and 'c' are coefficients of a quadratic equation : ax^2+bx+c=0.
    • Thread Starter
    Offline

    16
    ReputationRep:
    (Original post by JohnnyDavidson)
    Hi, you're factorising is wrong just after the line "ac =" (what exactly does this mean btw?)

    Name:  image.jpg
Views: 46
Size:  420.4 KB
    (Original post by notnek)
    ii.

    You have factorised -3y^2-3y to get -3y(y+3). This is incorrect - have another go.

    Your method will work but I would have taken out a factor of 3 from the quadratic (and moved everything to the other side) to make it simpler.
    Thanks - got it now
    Name:  14552349886831096247246.jpg
Views: 41
Size:  502.9 KB

    And ac is when ax^2 +bx +c
    Offline

    15
    ReputationRep:
    (Original post by IFoundWonderland)
    Thanks - got it now
    Name:  14552349886831096247246.jpg
Views: 41
Size:  502.9 KB

    And ac is when ax^2 +bx +c
    you have very neat workings !!
    Offline

    20
    ReputationRep:
    (Original post by JohnnyDavidson)
    Hi, you're factorising is wrong just after the line "ac =" (what exactly does this mean btw?)

    Name:  image.jpg
Views: 46
Size:  420.4 KB
    AC just means the first constant value e.g 2x^2-5x+3=0 -> Ax^2+Bx+C=0

    A = 2 from 2x^2 and C is the last value C = 3 .*. AC = A . C = 2x3 = 6 -> AC = 6

    It just helps writing down to figure out numbers that would factorise. i use the same method myself.
    • Thread Starter
    Offline

    16
    ReputationRep:
    (Original post by TeeEm)
    you have very neat workings !!
    Haha, thanks :ahee:

    I try to keep it as neat as possible because It makes it easier to check when I make mistakes although it tends to go to pot when the maths actually gets complicated and I'm doing things like further calculus or geometry.

    Idk why but this compliment made my day :lol:
    • TSR Support Team
    • Study Helper
    Offline

    20
    ReputationRep:
    (Original post by IFoundWonderland)
    Haha, thanks :ahee:

    I try to keep it as neat as possible because It makes it easier to check when I make mistakes although it tends to go to pot when the maths actually gets complicated and I'm doing things like further calculus or geometry.

    Idk why but this compliment made my day :lol:
    You like to keep inside the boxes!

    I had a student who would put everything in a box. Their calculus working was neat but quite strange to look at
    Offline

    21
    ReputationRep:
    (Original post by IFoundWonderland)
    Haha, thanks :ahee:

    I try to keep it as neat as possible because It makes it easier to check when I make mistakes although it tends to go to pot when the maths actually gets complicated and I'm doing things like further calculus or geometry.

    Idk why but this compliment made my day :lol:
    Small tip: for maths, it's incredibly helpful to leave a blank line between each line of working for complex calculations! It's makes correcting things, and finding errors much easier as well as just improving the general aesthetic, in my opinion! But yours is very nice as is!
    • Thread Starter
    Offline

    16
    ReputationRep:
    (Original post by notnek)
    You like to keep inside the boxes!

    I had a student who would put everything in a box. Their calculus working was neat but quite strange to look at
    Yess it makes it look so much nicer and everything is in line

    I keep everything in boxes for calculus too but that squiggly line thing at the beginning that shows it's integration (idk what it's called) takes up three boxes height wise and two width wise, so I use so much paper :argh:
    • Thread Starter
    Offline

    16
    ReputationRep:
    (Original post by Zacken)
    Small tip: for maths, it's incredibly helpful to leave a blank line between each line of working for complex calculations! It's makes correcting things, and finding errors much easier as well as just improving the general aesthetic, in my opinion! But yours is very nice as is!
    I know, but I waste enough paper as it is :hide:
 
 
 
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • Poll
    How are your GCSEs going so far?
    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
  • See more of what you like on The Student Room

    You can personalise what you see on TSR. Tell us a little about yourself to get started.

  • 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

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