maths question

[mattheman]

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(1)2x+3y=-1
(2)3x-2y=5

(3) 3*2x +3*3y= 3*-1
(4) 6x+ 9y=-3
(5) 2*3x-2*2y=2*5
(6) 6x-4y=10

so now i have
6x+9y=-3
6x-4y=10
0- 5y=-13

-13/5=-2.6
y=2.6

2x+3*-2.6=-3
2x+ -2.6=-3
-2.6- -3= .4
x=.2

just dosent add up

 

[Grrrrr]

so now i have
6x+9y=-3
6x-4y=10
0- 5y=-13

This part is wrong, it should be 13y = -13

 

[Hxc]

Simultanious equasions yes?

2x+3y=-1
3x-2y=5

2y=3x-5
y=1.5x-2.5

2x+3(1.5x-2.5)=-1
2x+4.5x-7.5=-1
6.5x=6.5
x=1

when x=1
2+3y=-1
3y=-3
y=-1

test on other equasion
x=1 y=-1
3x-2y=5
3-(-2)=5

 

[mattheman]

Simultanious equasions yes?

2x+3y=-1
3x-2y=5

2y=3x-5
y=1.5x-2.5

2x+3(1.5x-2.5)=-1
2x+4.5x-7.5=-1
6.5x=6.5
x=1

when x=1
2+3y=-1
3y=-3
y=-1

test on other equasion
x=1 y=-1
3x-2y=5
3-(-2)=5

thx
lol small error,

complete the square

y=2x^2-3x-1

y= 2{ x^2-3/2x}-1
x=(3/4) (/16

y=2{x^-3/2 x+ 9/16}-1-9/8
y=2(x-3/4)^2 -17/8

x=3/4 min point y = -17/8


but i did it again and it gave me

2{x^2(3/2)^2 x -(1/2)^2 +(3/2)^2

2(x-3/2)^2 -1/2 -9/4

2(x-3/2)^2 -2/4 -9/4=11/4

x=3/2 2x11= 22/4= 11/2