Final answer:
To clear parentheses and combine like terms, the expression (20x-15) - (7x-18) can be simplified to 13x + 3.
Step-by-step explanation:
To clear parentheses and combine like terms, we apply the distributive property and combine like terms within the parentheses.
So, (20x-15) - (7x-18) becomes 20x - 15 - 7x + 18.
Combining like terms, we have 20x - 7x - 15 + 18 = 13x + 3.
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