Question 414513
"how to solve this equation 5z2 - 15z = 0"


5z^2 - 15z = 0 
5z(z - 3) = 0 {factored out the greatest common factor, 5z}
5z = 0 or z - 3 = 0  {set each factor equal to 0}
z = 0 or z = 3 {solved each equation for z}
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