Question

Proszę i rozwiązanie tego na dzisiaj.
14.
e)
{2x -y = 1
{x +2y = 13
f)
{x+y = 10
{x-2y= -5
g)
{6a - 7b = -5
{2a +5b = -9
h)
{10s +20t=0
{s +1 =-1
15.
b)
{x-y=0
{2x+¼y = 2¼

Answer 1

E)
{2x -y = 1
{x +2y = 13 /razy (-2)
[2x-y=1
[-2x-4y=-26 stronami dodajesz
-5y=-25- :(-5)
y=5

[2x-y=1
[2x-5=1
2x=5-1
2x=6/ :2
x= 3

f)
{x+y = 10
{x-2y= -5 /razy (-1)
[x+y=10
[-x+2y=5 stronami dodajesz
3y=15 / :3
y=5

[x+y=10
[x+5=10
x=10-5
x=5

g)
{6a - 7b = -5
{2a +5b = -9/* (-3)
[6a-7b=-5
[-6a-15b=27 stronami dodajesz
-22b=22 / :(-22)
b=-1

6a-7razy(-1)-5
6a+7-5
6a=-5-7
6a=-12/ 6
a= -2