Need help with math Algebra 1?!?

Question

Solve each system by subsitution. Check your answer.

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

2. y=x-4
y=-x+2

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

ok thank you for the people who helepd me! I wasnt asking to give me the answers and cheat, i jsut needed the help and thats what the homework help section on Y/A! is for right?

Answer 1

1.) x - 2 = 4x + 1
-> -3 = 3x
-> x = -1

2.) x - 4 = -x + 2
-> 2x = 6
-> x = 3

3.) 3x + 1 = 5x - 3
-> 4 = 2x
-> x = 2

Answer 2

1) y=x-2 then 4x+1=x-2 because you substitute the y with the 4x-2 because they are equal. then you need to get all your xs on one side. 4x-x=-2-1 they change signs (+ or -) because really you are subtracting or adding to both sides. Then you add or subtract because they are first in the order of operations. So you get 3x=-3. Then you need to get the 3x to turn into just x so divide both sides by three. x=-3. Tada! so that is X now take that information and plug it into one of the original equations. Let's do the first but it doesn't really matter. So we get y=(-3)-2. (-3) used to be x. So now simplify for y=-5. And that's it. X=-3 Y=-5

2) again let's substitute the y in the first equation with the -x+2 in the second. They are equal to each other. (It's like saying "one" and "1", it's the same thing.) So we get
-x+2=x-4. Now we need your xs on one side. I like the left. So we subtract x from both and subtract two from both also. We get -x-x=-4-2. Again they change signs. Now we need to simplify some to get -2x=-6. Now we need to divide both sides by -2 to get x all alone. x=3 So let's put that into an original equation. y=(3)-4. That turns out to be y=-1 right? So that's it. X=3 and Y=-1

3) I'll leave this one up to you. Good luck.

Answer 3

Well, you can substitute the value of y from one equation into the other equation in the system. Then you wind up with one equation, with only the x variable. You solve this, and then find y. In equation system 1, 4x+1 = x-2, doing the substitution. Then 3x = -3 and x= -1. From either equation y= -3. Since both equation yield the same answer for y, this is a sufficient check.

Answer 4

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

4x + 1 = x - 2

3x = -3

x = -1

y = -1 - 2

y = -3

check:

-3 = -1 - 2

-3 = -3


-3 = 4(-1) + 1

-3 = -4 + 1

-3 = -3


2. y=x-4
y=-x+2

-x + 2 = x - 4

6 = 2 x

3 = x

y = -3 + 2

y = -1


check:

-1 = 3 - 4

-1 = -1


-1 = -3 + 2

-1 = -1


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


5x - 3 = 3x + 1

2x = 4

x = 2

y = 3*2 + 1

y = 6 + 1

y = 7


check:

7 = 3*2 + 1

7= 6 + 1

7 = 7


7 = 5*2 - 3

7 = 10 - 3

7 = 7

Answer 5

I would start with the teacher for Algebra 1, tell them your situation and they may be able to help you. Tell them you really love math too, that always helps. Guidance folks would be the next best bet. If neither of those work, then get your parents on the phone to the school, a little whining by parents goes a long way to getting what you want at school.

Answer 6

1. you know that y = x-2
so you can replace y with x-2 on the second equation
x-2 = 4x +1
solve for x
x = -1
plug -1 in for x on either equation
y= (-1) - 2
y = -3

to check your answer plug x and y into each equation and see if it holds true

-3 = -1-2
-3 = -3 correct

-3 = 4(-1) +1
-3 = -3 correct

2.same thing, substitute x-4 in for y on the second equation
x-4 = -x+2
solve for x

3. again.. same thing, substitute 3x+1 in for y on the second equation
3x +1 = 5x - 3

Answer 7

You simply substitute what y is in for y. So for number one, it says that y equals those two things, right? Well, move that means that if they both equal y, then they equal each other!

4x+1=x-2

combine like terms, and isolate x,

3x=-3

And voila!

x = -1

Or, you can isolate x. On number two, you'd add 4 to both sides, like so

y=x-4 > y+4=x-4+4 > y+4=x

So now you have x. Put x in the bottom equation.

y=-(y+4)+2

You need to make both y and 4 negative, because of distribution.

y=-y-4+2

Combine like terms

2y=-2

and voila!

y=-1

And same thing for 3.

3x+1=5x-3

-2x=-2

x=1

If I took all this time to write this out, don't I deserve best answer?

Answer 8

set each equal to each other and then solve for x:
x-2=4x+1
-x -x
-2=3x+1
-1 -1
-3=3x
divide by the +3 and x=-1

Answer 9

1. y = x-2, substitute this into the 2nd equation for y

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

2. y=x-4, again substitute this into the 2nd equation for y

y = -x+2
x-4 = -x+2
2x = 6
x = 3

3. y=3x+1, substitute this into the 2nd equation for y once more

y = 5x-3
3x+1 = 5x-3
4 = 2x
x = 2

Answer 10

Just pick something for x to equal. If you let x equal... 5. Then

1.) Y = 5-2 = 3
y=4(5)+1 = 21

2.) y=5-4 = 1
y = -5+2 = -3

3.) y == 3(5)+1 = 16
y=5(5)-3= 22