I am so lost on this Please help?

Question

Solve the following systems by substitution

4x - 12y = 5
-x + 3y = -1

Answer 1

4x - 12y = 5
-x + 3y = -1

-x = -1 – 3y
X = 1 + 3y

4(1+3y) – 12y = 5
4+12y-12y=5
4-0y=5
4=5

The answer is: NO SOLUTION.

Answer 2

This is easy.

You first need to isolate (or find) what x or y is worth. You use either equation.

I'm sure you know how to do this. The easiest (or crudest) way, (using the 1st equation) wold look like this:

(4x divided by 4) -(12y divided by 4) = 5 (divided by 4)

In other words, 4x/4 - 12y/4 = 5/4

(Each part of the equation is divided by 4.)

That gives you what x is worth:

x -3y = 5/4.

ARe you with me so far? Don';t go any further til you understnad what I just did: you just isolated x. You can rearrange the equation, so that x= 5/4 + 3y.

Got that? x = 5/4+3y. (You just added 3y to each side of that equation.

------------------------------------------

Now, you can plug that little jewel into either of the 2 equations: let's put it into the 2nd on,e just for fun:

You have:

-x + 3y = -1.

Let''s clean that up a bit to make it easier to understand. Add x to each side of the equation. Now you have 3y = -1 +x. OK?

Now add 1 to each side of the equation. That gives you 3y = x.

Or, x = 3y. Easy! You're almost done!!

Now you can plug that into anywhere!!!:

Try it in the first equation: 4(3y) - 12y =5.

That gives you 12y -12y =5.

Answer 3

Er, the second one you should get it. -x+3y is simple. x=4. So it should appear to be -4+3y=-1. Add 4 to each side, so -4+4=0 and -1+4=3, so it'll be 3y=3. Divide both sides by 3, and you get y=1.

First one is a bit crazier for me... 4x-12y=5. You could try guess and check to find it. I guess and check and I found x to be 4.25. Try 4*4.25=17. Substitute y with 1, so it becomes 17-12=5. I'm not sure, I could be wrong.

Answer 4

4x - 12y = 5
-x + 3y = -1 (4)= -4x-12y=-4
4x+12y=5
0=1
no solution

Answer 5

Equations like these are easier to understand if you consider the equals sign to be kind of like a balance beam that you want to keep level. Therefore, if you do something to one side you have to do it to the other.

Answer 6

?????????????????????????????????????????????