SOLUTION: -4x+9y=9 x-3y=-6 how do this problem by elimination?

Algebra.Com
Question 264568: -4x+9y=9
x-3y=-6
how do this problem by elimination?

Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!

Start with the given system of equations:



Multiply the both sides of the second equation by 3.


Distribute and multiply.


So we have the new system of equations:



Now add the equations together. You can do this by simply adding the two left sides and the two right sides separately like this:





Group like terms.


Combine like terms.


Simplify.


Divide both sides by to isolate .


Reduce.


------------------------------------------------------------------


Now go back to the first equation.


Plug in .


Multiply.


Add to both sides.


Combine like terms on the right side.


Divide both sides by to isolate .


Reduce.


So the solutions are and .


Which form the ordered pair .


This means that the system is consistent and independent.


Notice when we graph the equations, we see that they intersect at . So this visually verifies our answer.


Graph of (red) and (green)

RELATED QUESTIONS

Solve each system by elimination: –x + 3y = 6 x – 9y = 9 Any help would be... (answered by checkley77)
Solve by elimination: -x+3y=6... (answered by checkley77)
Please help me finish solving problem. Solve by the substitution method. 4x+3y= -9... (answered by stanbon)
How do you solve this by elimination: 2x + 3y - z = -8 x - y - z = -2 -4x + 3y + z = (answered by Greenfinch)
how do you solve this problem with elimination? 4x+3y=24... (answered by Susan-math)
-4x+9y=9 x-3y=-6 I have to solve for x and y using... (answered by Alan3354,Fombitz)
it says to solve with elimination -4x+9y=9... (answered by ikleyn)
How do you solve this by graphing? 3y=3x-6... (answered by xcentaur)
The question tells me to solve this system of equations using any method: -4x+9y=9... (answered by jorel555)