Can Anyone help me who is good at math?

Question

My friend and I have these math problems but we need some help to work them..Here are a few problems: solve each system of linear equations by using substitution

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


2.) 2x-y=7
6x-3y=14



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

Answer 1

1)so easy,
x=-12 , y=7

2) y=-14/0=NO ANSWER
x=NO ANSWER

3)so easy too,
x=-2 ,y=-4

by the way GOOD LUCK

Answer 2

When solving a linear system by substitution, you will want to get one of the variables equal to an expression. For example:

7x-21y=7
4x+16y=8
We want to get a variable alone on one side. Lets take the first equation and solve for x.

4x+16y=8, divide both sides by 4
4x/4+16y/4=8/4, the 4s with the x cancel
x+4y=2, subtract 4y from both sides
x+4y-4y=2-4y
x=2-4y

Take this answer and substitute it into the first equation.

7x-21y=7, substitute 2-4y in for any x in the equation
7(2-4y)-21y=7, do the multiplication
14-28y-21y=7, do the addition
14-49y=7, subtract 14 from both sides
14-49y-14=7-14, do the math
-49y=-7, divide both sides by -49
-49y/-49=-7/-49, the left side 49s cancel
y=-7/-49, reduce the left side, -7 is a common factor
y=1/7

Now you can sustitute this back into either equation to get an answer for x. It is wise to substitute into both equations, since that if the x value is the same, you have not made a mistake.

Hope this helps.

Answer 3

x+2y=2
-x
2y=2-x
/2*/2*/2
y=1-x/2

2x+3y=-3
PLUG IT IN
2x+3(1-x/2)=-3
DISTRIBUTE
2x+3-3/2x=-3
2x+3-1.5x=3
.5x+2=3
x=.5
THAT'S 1 ANSWER

2x+3y=-3
PLUG IT IN
2(.5)+3y=3
1+3y=3
3y=2
---*---
/3**/3
y=2/3

THAT'S THE APPROACH!

Answer 4

1. x = 2- 2y
2(2 - 2y) + 3y = -3
4 - 4y + 3y = -3
4 - y = -3
-y = -7
y = 7
x = 2 - 2(7)
x = -12

Answer 5

ok well substitution you need to solve for one variable first
x+2y=2
x=2-2y
substitute for x
2 (2-2y) + 2y =2
4-4y+2y=2
4-2y=2
-2y=-2
y=1

now substitute y=1 in to the an equation
I chose x= 2-2y
so x=0


hope this helps as a model so you can finish your homework

Answer 6

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

Answer 7

Is it that you don't know how to do the problems, or that you just don't want to do them?

If it's because you don't know how I can explain one, and you'll be able to do the last two.

Answer 8

me + you = 2

Answer 9

"your friend" and YOU should do your own work...you'll never learn the concept by asking us to do it for you...we can't taje the test for you, and tests are usually worth more than homework in your grade!

Answer 10

http://www.math.com