3x + 4y = 4

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This can easily be solved by substitution…first, solve the first equation for x.

x + 2y = 0 —> x = -2y

Now plug x = -2y into the second equation like this:

3x + 4y = 4

3(-2y) + 4y = 4 (substitute -2y in for x)

-6y + 4y = 4 (combine like terms)

-2y = 4 (divide both sides by -2)

y = -2 (answer!)

Now plug y = -2 into either equation, let’s choose the second one.

3x + 4y = 4…where y = -2

3x + 4(-2) = 4 (substitute -2 in for y)

3x – 8 = 4 (add 8 to both sides)

3x = 12 (divide both sides by 3)

x = 4 (answer!)

Therefore, x = 4 and y = -2.

I hope this helps! 🙂

-2y -2y therefore x = -2y

3(-2y) + 4y = 4

-6y + 4y = 4

-2y = 4

y = -2

x + 2(-2) = 0

x – 4 = 0

+4 +4

x = 4

I promise this is correct. I am a math major. Email me if you need more help or have any questions

x=4 y=-2

3x+4y=4 x=1 y=3

Glad I could help!

we need to equal atleast one variable. so,

We multiply x+2y = 0 with 2

and 3x+4=4 with 1

then we get

2(x+2y=0) = 2x +4y =0 (1)….

1(3x+4y=4)= 3x +4y =4 (2)……

now subtracting (2) from (1), we get

-x = -4

so, x=4

now putting the value of x in (1),we get

4+2y=0

2y=0 – 4

2y= -4

y= -4/2

y= -2

3(-2y)+4y=4

-6y+4y=4

-2y=4

y=-2

x=-2(-2)

x=4

x=4, y=-2