SOLUTION: I don't understand how to do this problem?
3x+y=5
-2x+3y=4
Algebra.Com
Question 168961: I don't understand how to do this problem?
3x+y=5
-2x+3y=4
Found 3 solutions by josmiceli, stanbon, Electrified_Levi:
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
(1)
(2)
This is 2 equations with 2 unknowns, so it's solvable
Multiply (1) by and subtract (2) from (1)
To subtract, change all the signs of (2) to minus
Now I'll rewrite these
The result is:
Substitute this result back in (1)
(1)
(1)
The solutions are x = 1 and y = 2
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
3x+y=5
-2x+3y=4
--------------
Multiply thru the 1st equation by 3:
9x+3y = 15
-2x+3y = 4
---------------
Subtract the 2nd from the 1st to get:
11x = 11
X = 1
-----------
Substitute this into 3x+y=5 to solve for "y":
3*1 + y = 5
y = 2
---------------
Ans: (1,2)
================
Cheers,
Stan H.
Answer by Electrified_Levi(103) (Show Source): You can put this solution on YOUR website!
Hi, Hope I can help,
.
3x+y=5
-2x+3y=4
.
There are several ways to solving these systems of equations, I will show you an overall easy way of doing it
.
First, solve for a letter, usually the easiest one, we will solve for "y" in both equations
.
First equation, , we need to move "3x" to the right side
.
= = or , if we rearrange it.
.
Our first answer is
.
Let us solve for "y" in the second equation,
.
, first we need to move (-2x) to the right side
.
= = or , rearranging it
.
, now we need to divide each side by "3" to get "y"
.
= =
.
is our second answer
.
Since "y" equals one number both of our answers will equal each other
.
First answer =
.
Second answer =
.
These two answers will equal each other
.
= , we will use cross- multiplication
.
=
.
, rearranging the left side
.
, now we can use the distribution method
.
=
.
Remember the negative and positive signs
.
.
Now we can solve for "x", let us move (-9x) to the right side
.
= = , now we need to move "4" to the left side
.
= = , now we can divide each side to find "x"
.
= = , , you can check by replacing "x" with "1" in the equation
.
= = = = ( True )
.
, to find "y", replace "x" with "1" in one of the two original equations
.
3x+y=5
-2x+3y=4
.
We will use the first equation
.
= = , now we will move "3" to the right side
.
=
.
.
.
We can check our answers by replacing both "x" and "y" in the two original equations. ( x = 1 ) ( y = 2 )
.
= = = ( True )
.
= = = ( True )
.
.
.
A solution set is in the form (x,y), our solution set is ( 1, 2 )
.
Hope I helped, Levi
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