Question

e) { 10(y+2)+3(x-5)=x-5

{ 25(y+2)+3(x-5)=-10

f) {2(2x-y)+3(x+3y)=42

{5(x+3y)-8(2x-y)=-32

PLIS POMÓŻCIE DAJĘ NAJ

Answer 1

e)

I { 10(y+2)+3(x-5)=x-5

II  { 25(y+2)+3(x-5)=-10

 

10y+20+3x-15=x-5

25y+50+3x-15=-10

 

10y+3x-x+10=0

25y+3x+45=0

 

10y+2x=-10

25y+3x=-45

 

35y+5x=-55

5x=-55-35y/5

x=-11-7y

rozw I

10y+2(-11-7y)=-10

10y-22-14y=-10

-4y=-10+22

-4y=12

y=-3

podstawiam do x

x=-11-7y

x=-11-7*(-3)

x=-11-21

x=-32

 

x=-32

y=-3

 

 

f)  I {2(2x-y)+3(x+3y)=42

II {5(x+3y)-8(2x-y)=-32

 

4x-2y+3x+9y=42

5x+15y-16x+8y=-32

 

7x+7y=42

-11x+23y=-32

 

I 7x=42-7y/7

x=6-y

rozw II

-11x+23y=-32

-11(6-y)+23y=-32

-66+11y+23y=-32

34y=-32+66

34y=34

y=1

podstawiam do x

x=6-y

x=6-1

x=5

 

x=5

y=1