Posted by m on Monday, February 21, 2011 at 7:57pm.
These simultaneous equations can be solved most of the time by either substitution or by elimination. We will try elimination here, since I see 5y in both equations.
3x-5y=-2....(1)
5y-2x=-2....(2)
Rearrange to line up x and y in columns
3x-5y=-2...(1a)
-2x+5y=-2...(2a)
Add the two equations:
3x-2x -5y+5y = -2 -2
simplify to get
x = -4 ... (3)
Substitute (3) into (1) to get
3(-4)-5y=-2
-5y = -2 + 12
-5y = 10
y = 10 / (-5) = -2 ..(4)
(3) and (4) give the final answer, but we still have one more step to do: check!
Substitute (3) and (4) into (1) and (2) to get
3(-4)-5(-2)
=-12+10
=-2 from (1) OK
5(-2)-2(-4)
=-10+8
=-2 from (2) OK
Related Questions
Algebra - Checking a few answers to some algebra problems: 1.Find the slope of ...
algebra - 3x+5y=0 2x-5y=-9 idk how 2 solve it then graph it my teacher eont help...
algebra - Solve the system of equations: what is the y-value in the solution? ...
Algebra - How come when you find the square of the binomial (2x-5y)^2, the ...
Algebra - Solve using the elimination method. Show your work. If the system has ...
Algebra - I'm really lose with this problem...HELP Using Cramer Rule If D=O ...
Algebra - Elimination method: x+5y=-13 2x-5y=-19 ( , )
algebra - Solve by the linear combination method (with or without multiplication...
algebra - |5y-2| > 2 ok since it is greater than you would have to ...
Algebra - I am great at math but for some reason can not wrap my brain around ...
For Further Reading
