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Explanation:
Set each factor equal to zero and solve for x. This is using the zero product property.
(2x+1)(x-3) = 0
2x+1 = 0 or x-3 = 0
2x = -1 or x = 3
x = -1/2 or x = 3
If you graphed the function, you should see that it crosses the x axis at -1/2 and at 3.
