Odpowiedzi

2010-01-26T18:47:34+01:00
A) 6(x + y) = 10y
y - x = 0,5

6x + 6y = 10y | -6y
y - x = O,5 | + x
6x = 4y
y = 0,5 + x
6x = 4 (0,5 + x)
y = 0,5 + x
6x = 2 + 4x | -4x
y = 0,5 + x
2x = 2 | :2
y = 0,5 + x
x = 1
y = 0,5 + 1
x = 1
y = 1,5
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2010-01-26T18:52:14+01:00
A
{6(x+y)=10y
{y-x=0,5
[6x+6y=10y
[-x+y=0,5
{6x+6y-10y=0
{-x+y=0,5
[6x-4y=0
[-x+y=0,5/*6
{6x-4y=0
{-6x+6y=3
~~~~~~~~~~
_____2y=3/:2
_____y=1,5
6x-4y=0
6x-4*1,5=0
6x-6=0
6x=6/:6
x=1
{x=1
{y=1,5
b
{y-8x=0,8y
{4x+5y=5,1
[-8x+y-0,8y=0
[4x+5y=5,1
{-8x+0,2y=0
{4x+5y=5,1/*2
[-8x+0,2y=0
[8x+10y=10,2
`````````````
____10,2y=10,2/:10,2
_______y=1
-8x+0,2y=0
-8x+0,2*1=0
-8x+0,2=0
-8x=-0,2/:(-8)
__x=0,025
c
{2y+5x=6x
{3y+4x=7 ¾______7 ³/₄mozna zapisac ³¹/₄ to 7,75
[5x-6x+2y=0
[4x+3y=7,75
{-x+2y=0/*4
{4x+3y=7,75
[-4x+8y=0
[4x+3y=7,75
`````````````
_____11y=7,75/:11
______y≈1,409
-x+2y=0
-x+2*1,409=0
-x+2,818=0
-x=-2,818/:(-1)
x=2,818
d
{1,5y-6x=4,5y
{4y+9x=11⅔
[-6x+1,5y-4,5y=0
[9x+4y=³⁵/₃
{-6x-3y=0/*3
{9x+4y=11,666/*2
[-18x-9y=0
[18x+8y=23,332
````````````````
____-y=23,332/8(-1)
_____y=-23,332
-6x-3y=0
-6x-3*(-23,332)=0
-6x+69,996=0
-6x=-69,996/:(-6)
__x≈11,666

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