SOLUTION: solve the system by the elimination method: x+9y=66 and -x+9y=60

Algebra.Com
Question 236583: solve the system by the elimination method: x+9y=66 and -x+9y=60
Answer by jim_thompson5910(35256)   (Show Source): You can put this solution on YOUR website!

Start with the given system of equations:



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.


Subtract from both sides.


Combine like terms on the right side.


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 the system by elimination method x=9y+8... (answered by mananth)
solve the system by elimination method x+8y=-16... (answered by checkley75)
Solve the following system of equations, using the elimination method: x - 2y = -12 (answered by TheInstructor)
Solve by the elimination method x+8y=54... (answered by jim_thompson5910)
Solve by the elimination method. 8x-y=69... (answered by nerdybill)
Solve the following problem using the elimination method: x+9y=75... (answered by algebrahouse.com)
solve the following system by any method {{{system( x=9/2*y+y, 2x-9y=14... (answered by ichudov)
Solve by the elimination method. 3x-9y=1 3x-9y=2 What is the solution of the... (answered by rapaljer)
solve the system x+y=2 and x-y=4 by the elimination... (answered by Fombitz)