



 
Millie, One of the important facts about our number system is that if you multiply two nonzero numbers the result is not zero. Hence if you multiply the two numbers (3x  4) and (5x + 2) and obtain an answer of zero then either (3x  4) is zero or (5x + 2) is zero. Hence the equation
leads to
Solve these two equations for x and this will give you the two values of x that give (3x  4)(5x + 2) = 0. Penny  


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