Solve each non-linear system
y = 2/x
y = 4x - 2
I found the X values to be 1, and -0.5
How do the find the X value that corresponds to the original half of the system, with no possibility of error?
What I did was make it from
y = 2/x
y = 4x - 2
to
2/x = 4x - 2
to
2 = 4x^2 - 2x
0 = 4x^2 - 2x - 2
Then used the quadratic formula for find the X values.
Now I just need to know how to determine which X values match up with which halves of the system so that I can find the RIGHT Y values.
Help me!Stuck on a question - Please look over my work and help me with the last step?
2/x = 4x - 2
4x虏 - 2x = 2
x虏 - 1/4x = 1/2 + (- 1/4)虏
x虏 - 1/4x = 8/16 + 1/16
(x - 1/4)虏 = 9/16
x - 1/4 = 卤 3/4
x = 3/4 + 1/4, x = 4/4, x = 1
x = - 3/4 + 1/4, x = - 2/4, x = - 1/2
Answer: x = 1, - 1/2
-----------
y = 2/1
y = 1
y = 4(1) - 2
y = 4 - 2
y = 2
y = 2/(- 1/2)
y = - 4
Answer: y = 2, - 4Stuck on a question - Please look over my work and help me with the last step?
The correct x-value must make the same y-value come up in BOTH equations.
This occurs when x is -0.5 like you solved for.
When x=1, both equations are not the same, which they are supposed to be, so this is Not a solution.
The only solution is x = -0.5, y = - 4. ( -0.5, -4 )
You have the ';Right'; x values that solve the system of equations. It's not a case of one value solves one equation and the other solves the other. Substitute the x values into either equation to find the y- values. Each x value will generate the same y-value in both equations.
Substituting x = 1 into the first equation:
y =2/1 = 2
and into the second equation:
y = 4-2 = 2
Substituting x = -0.5 into the first equation:
y = 2/(-.5) = -4
and into the second:
y = 4(-.5) - 2 = -2 - 2 = -4
What you have are the equations of a hyperbola and a straight line. The x and y values are the points of intersection of that hyperbola and the straight line which intersect at two points. The points solve both equations simultaneously - that's one reason a system of equations like that is also called a set of ';simultaneous'; equations.
There are TWO x values and TWO y values. Substitute each values of x into the equations you get TWO answers. BOTH answers are correct.
x = 1, y = 2
x = -0.5, y = -4
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