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    Hey any of you good people know this answer it is for my homework:

    2x=10-3y
    3x+ 19=4y

    Method and answer; i will be grateful
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    (Original post by Katchi_2003)
    Hey any of you good people know this answer it is for my homework:

    2x=10-3y
    3x+ 19=4y

    Method and answer; i will be grateful
    solve simultaneously.

    2x=10-3y x3
    3x=4y-19 x2

    6x=20-9y
    6x=8y-38

    0=58-17y
    y=58/17
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    (Original post by Katchi_2003)
    Hey any of you good people know this answer it is for my homework:

    2x=10-3y
    3x+ 19=4y

    Method and answer; i will be grateful
    6x = 30 - 9y
    6x = 8y - 38

    17y - 68 = 0 , y = 4
    2x = 10 - 3(4) = -2
    x = -1
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    thank you, can you show me the checking method
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    3y = 10-2x => y = (10-2x)/3

    Substitute this into other equation:

    4((10-2x)/3) = 3x + 19

    (40-8x)/3 = 3x + 19

    40-8x = 9x + 57
    40-57 = 17x => x = -1

    Then substitute into either of your original equations to get y.
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    bhaal 10 x 3 = 30
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    (Original post by Lucy)
    bhaal 10 x 3 = 30
    Whoops.........that was meant to test you other peeps. lol.
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    (Original post by Bhaal85)
    Whoops.........that was meant to test you other peeps. lol.

    Man i done it but the check doesnt work, can someone show me how its done with full method and working, i be grateful.
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    Ok this is what I did:

    First I rearranged the formulae:

    2x = 10-3y (1)
    3x = 4y-19 (2)

    Then I did the formula (1) times 3 to make:
    6x = 30 - 9y (3)

    and I multiplied the formula (2) by 2 to make:
    6x = 8y - 38 (4)

    Then I did formula (4) minus formula (3) to make:
    0 = 17y-68
    therefore 17y=68
    y = 4

    I substituted y into formula (1) to get:
    2x = -2
    therefore x = -1

    Substituted both values of x and y into (2) to check my values were correct.

    Hope this is a bit clearer
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    (Original post by Lucy)
    Ok this is what I did:

    First I rearranged the formulae:

    2x = 10-3y (1)
    3x = 4y-19 (2)

    Then I did the formula (1) times 3 to make:
    6x = 30 - 9y (3)

    and I multiplied the formula (2) by 2 to make:
    6x = 8y - 38 (4)

    Then I did formula (4) minus formula (3) to make:
    0 = 17y-68
    therefore 17y=68
    y = 4

    I substituted y into formula (1) to get:
    2x = -2
    therefore x = -1

    Substituted both values of x and y into (2) to check my values were correct.

    Hope this is a bit clearer

    I Solved it in my way that method is right i [email protected]

    2x+3y=10 > 1
    3x-4y=19 > 2

    >1 *4

    8x+12y = 40 >3

    >2* 3

    9x-12y=57 > 4

    8x+12y = 40 >3
    9x-12y =57 > 4

    4-3

    1x=17
    x=17

    subst in 1:

    34 + 3y = 10
    3y = -24
    y= -8

    x=17
    y= -8

    check in 2:

    51 - 32 = 19

    3x-4y=19

    thanks for all yr help
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    The formula you posted originally i.e. 3x +19 = 4y does not equal what you just posted now i.e. 3x - 4y = 19... it equals 3x - 4y = -19
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    (Original post by Bhaal85)
    solve simultaneously.

    2x=10-3y x3
    3x=4y-19 x2

    6x=20-9y
    6x=8y-38

    0=58-17y
    y=58/17
    AFTER THIS U ADD 17y to both sides so u have

    17y = 58

    then u divide by 17 so u r left with

    y= 58 divided by 17
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    (Original post by CHAD)
    AFTER THIS U ADD 17y to both sides so u have

    17y = 58

    then u divide by 17 so u r left with

    y= 58 divided by 17
    yeah, I know hence y=58/17. But its wrong, if you really look at it.
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    (Original post by CHAD)
    AFTER THIS U ADD 17y to both sides so u have

    17y = 58

    then u divide by 17 so u r left with

    y= 58 divided by 17
    We have already discovered that this is wrong as 2x=10-3y (x3) does not equal 6x = 20-9y therefore all the steps after that are incorrect (even though method is correct)
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    (Original post by Lucy)
    We have already discovered that this is wrong as 2x=10-3y (x3) does not equal 6x = 20-9y therefore all the steps after that are incorrect (even though method is correct)
    Like I said before, it was a test
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    Lol but now you've gone and confused everyone!
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    as u'r all talkin about maths..... is anyone doin the gcse maths c/wk where u have 2 find the difference of the products in a number grid??

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    (Original post by Saf!)
    as u'r all talkin about maths..... is anyone doin the gcse maths c/wk where u have 2 find the difference of the products in a number grid??

    nup.
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    (Original post by ShOcKzZ)
    nup.
    i know theres loads of u who have dun it!!! :mad:
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    Why did this question have "tricky" in the title??
 
 
 
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