3x+7y=1

2x+4y=0 and (2,3)

y=1, x=-2

and y=-2.5, x=6.5

Step-by-step explanation:

2x+4y=0. (-4y)

2x=-4y. (:2)

x=-2y. [1]

then 3x+7y=1 (subsitute from [1])

3 (-2y) + 7y=1

-6y+7y=1

y=1

then 3x+7y=1

3x+7 (1) = 1

3x+7=1

3x=1-7

3x=-6

x=-2

3x+7y=2

2x+4y=3

2x+4y=3

2x=3-4y

x=3/2-2y

then 3x+7y=2

3 (3/2-2y) + 7y=2

4.5-6y+7y=2

4.5+y=2

4.5+y-2=0

4.5-2=-y

2.5=-y

-2.5=y

then 2x+4y=3

2x+4 (-2.5) = 3

2x-10=3

2x=3+10

2x=13

x=13/2=6.5