Final answer:
To rewrite the expression 9x^2 - 45x by taking out the greatest common factor, the expression can be simplified to 9x(x - 5).
Step-by-step explanation:
To rewrite the expression 9x^2 - 45x by taking out the greatest common factor, we need to find the largest number or variable that can be divided evenly by both terms. In this case, the greatest common factor is 9x. Therefore, we can rewrite the expression as 9x(x - 5). The greatest common factor, 9x, is placed in front of the parenthesis.
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