Question

Pls 24/23 dau coroana️​

Answer 1

(f)

3x+y/3=-4

2x-2y/3=0

<=>

9x/3+y/3=-12/3

6x/3-2y/3=0

<=>

9x+y=-12

6x-2y=0 /:2

<=>

9x+y=-12

3x-y=0

<=>

9x+y=-12

y=3x

<=>

9x+3x=-12

y=3x

<=>

12x=-12 /:12

y=3x

<=>

x=-1

y=-3

(e)

-2x/5+y=0

3x-5y/2=10

<=>

-2x/5+5y/5=0

6x/2-5y/2=20/2

<=>

-2x+5y=0

6x-5y=20

<=>

-2x=-5y /:-2

6x-5y=20

<=>

x=5y/2

6*5y/2-5y=20

<=>

x=5y/2

30y/2-10y/2=40/2

<=>

x=5y/2

30y-10y=40

<=>

x=5y/2

20y=40 /:20

<=>

x=5y/2

y=2

<=>

x=5*2/2

y=2

<=>

x=5

y=2