Can someone step by step me through this algebra 1 problem?

Question

My math teacher goes too fast for me to learn.

x + 3y=2

x +4y=16

I really need to be taken through this. I have a quiz tomorrow and don't get it at all. The title is "Systems of equations using linear combinations" (incase you needed to know what process to use)

Please help.

Answer 1

This is a little difficult to explain, but I'll try.

To solve for x and y you first need to get rid of one of the variables.

The easiest way is to multiply one of the equations by a negative number. Since the coefficient for both the x's is 1 then you just multiply one of the equation by a negative and add them together.

x + 3y = 2

- (x + 4y) = - (16)

When you add them together the x's cancel so you get:

-y = -14

So you get y = 14.

Now that you have y, you can plug that back into either of the equations to solve for x.

Using the first one you get:

x + 3(14) = 2

x + 42 = 2

x = - 40

Hope this helps.

Answer 2

use the method of Elimination ..

so first, name the equation "x+3y=2"  .....(1)

and name the equation "x+4y=16"  .......(2)

so now you have :

x+3y=2 ....(1)

x+4y=16 ...(2)

now, is the eliminating ...see that both x's have no coefficient, so subtract them and you will be left with only the y's to solve for .

so

(1) - (2):

-y=-14

so y=14

now you can substitute the y into the first (or second whichever you wish to do it) equation..

x+3(14)=2

x+42=2

x=2-42

x=-40

(-40,14)

Answer 3

x + 3y = 2

x + 4y = 16

Rewrite as:

12x + 36y = 24 (multiply by 12)

-12x - 48y = -192 (multiply by -12)

-12y = -192 (subtract)

y = 16 (divide by -12)

To find out x:

12x + 36y = 24

12x + 36(16) = 24

12x + 576 = 24

12x = -552

x = -46

Double-checking answer:

12(-46) + 36(16) = 24

-552 + 576 = 24

Help?

http://answers.yahoo.com/question/index?...

Answer 4

its kind of long to explain, you can use one of 3 methods, graphing, substitution, or elimination. If you are unfamiliar with any of those, talk to your teach first thing tomorrow and ask him to explain the process

Answer 5

Okay this is really simple and easy! I'll show you.

x + 3y=2

x +4y=16

So you doing systems. Your trying to get rid of one variable. I would go get rid of the X in "x + 3y=2"

SO:

x + 3y=2

-1(x+3y=2) would be:

-x -3y = -2

SO

-x -3y = -2

x +4y=16

The X's cross out so it would be:

-3y = -2

4y=16

Now you add. So:

Y=14

Now you just plug 14 as Y in the orignal equations and your set =).

Answer 6

http://www.regentsprep.org/Regents/Math/...

I'm pretty sure this link will help (: