SOLUTION: 0.3x-0.2y=4 0.2x+0.5y=-3

Question 155953: 0.3x-0.2y=4
0.2x+0.5y=-3

Answer by Electrified_Levi(103) (Show Source): You can put this solution on YOUR website!
Hi, Hope I can help
.

.
If you are trying to find the solution to the two equations, this is the way I do it.
.
First, we will multiply each equation by 10(multiply each side of the two equations by 10)(you don't have to, but it will get rid of the decimal point)
.
We will multiply
.
First equation = = =
.
Second equation = = =
.
The two new equations are
.
First equation =
.
Second equation =
.
Now we can start solving
.
First, solve for a letter in each equation(doesn't matter which letter) we will solve for "x"
.
First equation =
.
We will move (-2y) to the right side
.
=
.
We will rearrange the right side
.
=
.
We will divide by "3" to get "x"
.
=
.
Our first answer =
.
Now we will solve our second equation
.
We will move "5y" to the right side
.
=
.
If we rearrange we will get
.
We need to divide by "2" to get "x"
.
=
.
Our second answer =
.
Our two answers we got are
.
Answer 1 =
.
Answer 2 =
.
We will now put the two answers together in an equation (since they equal the same letter "x", they equal each other)
.

.
Now we will start solving for "y", we will cross multiply
.

.
we will get
.
when we use distribution, we get
.
We will move (-15y) to the left
.
=
.

.
We will move the "80" to the right
.
=
.
We will now divide each side by "19" to get "y"
.
=
.
We found that "y" =
.
We can replace "y" with in one of our easier equations( one of the equations
.

.
We will use the first equation(replace "y" with
.

.
double negative
.

.
we will move to the right side
.
=
.
we need to change the "40" , 40 = , replace "40" with that number
.

.
=
.
No we will divide each side by "3" to get our answer
.
= =
.
Our "x" = , we can check our solution in one of our original equations(our very first two equations)
.
Equation 1 =
.
Equation 2 =
.
"x" =
.
"y" =
.
We will replace "x" and "y"
.
Equation 1 = ( 0.3 same as )(0.2 same as
.
=
.
(True)
.
We can replace "x" and "y" in our second equation ( 0.2 = , 0.5 = = ) ( we will use )
.

.
= True
.
"x" = or 7
.
"y" = or ( -8 )
.
solution set = (x,y), our solution set = (, )
.
Hope I helped,Levi
RELATED QUESTIONS
solve the homogeneous system: {2x+y+z=0 4x-5y+z=0 (answered by venugopalramana)

3x+5y=0 (answered by jim_thompson5910)

3x + 5y + 10 =0 (answered by checkley71)

3x+5y+10=0 (answered by HyperBrain)

3x-2y+4=0 (answered by nyc_function)

Slope 2x-5y=0 (answered by LilSkittleMd)

graph :... (answered by ewatrrr)

2x+5y = -1 x+2y =... (answered by gsmani_iyer,kiru_khandelwal)

5y+3=2y 5y-2y+3=0 3y+3=0 y+1=0... (answered by shyfaiza17)

3x-5y-4=0 and... (answered by problemsolver13)