Question 1029261
look at the denominator, what value/s of x make the denominator = 0 (points of discontinuity)
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x^2 +9x +20 = 0
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(x+5) * (x+4) = 0
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points of discontinuity are x = -5 and x = -4
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domain is all real values of x except for -5 and -4
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if x = 0, then y = 1/4 (y intercept)
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y = (x+5) / ( (x+5)*(x+4) ) = 1 / (x+4)
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x+4 = 1/y
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x = 1/y -4
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no x intercepts since y can not be = 0
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the discontinuity x = -5 can be removed but x = -4 cannot be removed
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note that we remove x = -5 by refining the function
y = (x+5) / ( (x+5)*(x+4) ) = 1 / (x+4)
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