Rozwiąż układ równań metodą podstawiania.
a.{ 3x + 2y = -3
7x + 2y = 1
b. { 2x - 3y = 7
4x + 1/2y = 1
c. {4x - 6y= 0
2/3x + 1/2y= 1/3
a)
{3x+2y=-3 /*(-1)
{7x+2y=1
{-3x-2y=3
{7x+2y=1
__________
4x=4 /:4
x=1
3*1+2y=-3
3+2y=-3
2y=-3-3
2y=-6 /:2
y=-3
b)
{2x-3y=7 /*(-2)
{4x+1/2y=1
{-4x+6y=-14
{4x+1/2y=1
_____________
6i1/2y=13
y=2
2x-3*2=7
2x-6=7
2x=7+6
x=6,5
c)
{4x-6y=0 /*1/12
{2/3x+1/2y=1/3
{1/3x-1/2y=0
{2/3x+1/2y=1/3
______________
x=1/3
1/3*1/3-1/2y=0
1/9-1/2y=0
-1/2y=-1/9
y=-1/9:(-1/2)
y=-1/9*(-2)
y=2/9