Chapter 3.4 : Solve Rational Equations and Inequalities
a) 4 / (x-5) = 3 / (x+4)
      4(x+4) = 3(x-5)
       4x-3x = -15-16
              x = -31

b) 4 / (x-5) < 3 / (x+4)
    [4 / (x-5)] - [3 / (x+4)] < 0
    (4x+16-3x+15) / (x-5)(x+4) < 0
     (x+31) / (x-5)(x+4) <0

    Find the f(x) < 0
 

Intervals	x< -31	-31 <x< -4	-4 < x < 5	x>5
(x+31)	-	+	+	+
(x-5)	-	-	-	+
(x+4)	-	-	+	+
Sign of f(x)	-	+	-	+

   Therefore, f(x) < 0 is x< -31 or -4 <x< 5


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Part 1

Part 2

Part 3