SOLUTION: Obtain the domain and range for the following equation: y= 3x-7/2x+8

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Question 30529: Obtain the domain and range for the following equation:
y= 3x-7/2x+8

Found 2 solutions by sdmmadam@yahoo.com, venugopalramana:
Answer by sdmmadam@yahoo.com(530) About Me  (Show Source):
You can put this solution on YOUR website!
y= 3x-7/2x+8 ----(1)
Since division by zero is not defined
(2x+8) SHOULD NOT BE ZERO
And (2x+8)willbe zero then 2x = -8 which implies x = -82 = -4
Therefore for (1) to exist, x SHOULD NOT BE (-4)
Therefore (1) is defined for all x excepting (-4)
Therefore our answer set is
the complement of the singleton set {-4} in R the real number system

Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
IS IT ...y= (3x-7)/(2x+8)....PLEASE PUT BRACKETS TO MAKE IT CLEAR....AS YOU PUT IT ,IT MAY MEAN
1...y= (3x)-7/(2x)+8...OR
2...y= (3x)-(7/2)x+ 8....OR
3...y= (3x) - 7/(2x) + 8........ETC.....
GOING BY y= (3x-7)/(2x+8)....SINCE DIVISION BY ZERO IS PROHIBITED IN MATHS...DOMAIN IS RESTRICTED BY 2X+8=0 OR X=-4...SO ALL VALUES OF X
EXCEPT X=-4 IS THE DOMAIN.....
FOR THIS DOMAIN WE FIND THAT AS X TENDS TO INFINITY...
Y TENDS TO 3/2...SINCE
y= (3x-7)/(2x+8) = {3-(7/X)}/{2+8/X)}...AS X TENDS TO INFINITY ....
Y= (3-0)/(2+0)=3/2
SO RANGE IS 3/2 TO INFINITY AS X VARIES FROM - INFINITY TO -4 AND
3/2 TO -INFINITY AS X VARIES FROM -4 TO INFINITY.
SEE GRAPH BELOW TO UNDERSTAND
+graph%28+600%2C+600%2C+-50%2C+50%2C+-5%2C+5%2C+%283x-7%29%2F%282x%2B8%29%29+