Question 26897
3(2x+5) is basically distribution of the 3 to the numbers inside the parenthesis. 3x2=6x and 3x5=10. Finished, it would be: 6x+10. 
On 3x+2x you are just combining like terms. Since the 3 and 2 both have a x, you can add them together: 5x. 


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