Question

Rozwiąż układ równań metodą podstawiania:
a)x-3y=2
2x+y=-3

b)-3x+2y=-7
4x-y=11

Answer 1

A) x-3y=2
2x+y=-3/*3
x-3y=2
6x+3y=-9
___________
7x=-7/:1
x=-1

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

b) -3x+2y=-7
4x-y=11/*2
-3x+2y=-7
8x-2y=22
____________
5x=15/:5
x=3

4x-y=11
-y=11-12
-y=-1/*-1
y=1

Answer 2

A) x-3y=2
2x+y=-3/*3
x-3y=2
6x+3y=-9

7x=-7/:1
x=-1

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

b) -3x+2y=-7
4x-y=11/*2
-3x+2y=-7
8x-2y=22

5x=15/:5
x=3

4x-y=11
-y=11-12
-y=-1/*-1
y=1

Licze na naj;*

Answer 3

1)
x=2+3y
2x+y=-3
2(2+3y)+y=-3
4+6y+y=-3
7y=-3-4
7y=-7/7
y=-1

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

2)
-3x+2y=-7
4x-y=11
-y=11-4x/(-1)
y=-11+4x

-3x+2(-11+4X)=-7
-3x-22+8x=-7
5x=-7+22
5x=15/5
x=3

4x-y=11
4*3-y=11
12-y=11
y=1