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Factoring the numerator: 4x2−12x=4x(x−3)
Factoring the denominator: 3x2+15x=3x(x+5)
Reducing to lowest terms:
4x2−12x3x2+15x=4x(x−3)3x(x+5)=4(x−3)3(x+5)
Finding excluded values: x≠−5