Algebra help asap please show how to do in steps in each problem thanks

1. 2x + 7y = 3
x=1-4y

2. y = 5x
2x + 3y =34

3. 3x - 5y = 11
x - 3y = 1

4. 2x - y = 8
y = 2x - 3

5. 1/3x - y = 2
x - 3y = 6

2x + 7y = 3
Plug in x = 1-4y
2(1 - 4y) + 7y = 3
2 - 8y + 7y = 3
2 - y = 3
-y = -1
y = 1

x = 1 - 4y
plug in y
x = 1 - 4*1
x = -3

x=-3 , y = 1

2.

y = 5x
2x + 3y = 34

plug in y
2x + 3(5x) = 34
2x + 15x = 34
17x = 34
17x/17 = 34/17
x = 2

Now solve for y
y=5x
y = 5*2
y = 10

x=2, y =10

3.

3x - 5y = 11
x - 3y = 1

now variable can just be plugging in
you must solve of the equations above for one variable
x - 3y = 1
becomes x = 3y + 1

Now plug in x
3(3y + 1) - 5y = 11
9y + 3 - 5y = 11
4y + 3 = 11
4y = 8
y = 2

Plug in for x
we found x = 3y + 1
x = 3*2 + 1
x = 7

x=7, y =2

4.

2x - y = 8
y = 2x- 3

plug in for y
2x - (2x - 3) = 8
2x - 2x + 3 = 8 (make sure to carry in the negative, it is like having - 1 there)
3=8 which is not true (null space, no solution)

5.

1/3 x - y = 2
x - 3y = 6

need to isolate one variable like before
x = 3y + 6

now plug in to equation

1/3 (3y +6) - y = 2
y + 2 -y = 2
the y's cancel one another
2 = 2 (this is true statement, so all real solutions)

All real solutions

I'm just going to pretend that you asked us to solve a system of equations, because you did not make it very clear...
1. 2x + 7y = 3
2( -x - 4y = -1)
= 2x + 7y = 3
+-2x - 8y = -2
= -1y = 1
y = -1
Plug that back into one of the equations
2x + 7(-1) = 3
2x - 7 = 3
2x = 10
x = 5

I hope you at least could understand my work. I'm not going to do the rest because typing it all out is a **** ton of work and you should probably do some of your own homework.

PS: to Someone, your number one is wrong.
2-y = 3
Subtract 2 from each side and you get -y=1
Therefore y= -1
So your x is wrong also.