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Maths Question ( Tricky)
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Katchi_2003
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#1
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
2x=10-3y
3x+ 19=4y
Method and answer; i will be grateful
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Bhaal85
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#2
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#2
(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
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
2x=10-3y x3
3x=4y-19 x2
6x=20-9y
6x=8y-38
0=58-17y
y=58/17
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Sir I. Newton
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#3
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#3
(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
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 = 8y - 38
17y - 68 = 0 , y = 4
2x = 10 - 3(4) = -2
x = -1
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Katchi_2003
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#4
Nylex
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#5
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#5
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.
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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Lucy
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#6
Bhaal85
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#7
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#7
(Original post by Lucy)
bhaal 10 x 3 = 30
bhaal 10 x 3 = 30
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Katchi_2003
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#8
(Original post by Bhaal85)
Whoops.........that was meant to test you other peeps. lol.
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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Lucy
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#9
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#9
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
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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Katchi_2003
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#10
(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
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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Lucy
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#11
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#11
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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CHAD
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#12
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#12
(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
solve simultaneously.
2x=10-3y x3
3x=4y-19 x2
6x=20-9y
6x=8y-38
0=58-17y
y=58/17
17y = 58
then u divide by 17 so u r left with
y= 58 divided by 17
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Bhaal85
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#13
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#13
(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
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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Lucy
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#14
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#14
(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
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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Bhaal85
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#15
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#15
(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)
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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Lucy
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#16
Saf!
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#17
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#17
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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ShOcKzZ
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#18
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#18
(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??
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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Saf!
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#19
Nylex
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#20
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