4a+5a= 9a +(-3) correct as follows 4a+5a-3=9a+(-3). You forgot the -3 on the left side.
am i right? You are correct...with slight changes in your process in getting the answer.
4a-3+5a=4a+5a-3=(4+5)a-3=9a-3
Answer can be 9a-3 or 9a+(-3).
I hope the above steps and explanation were helpful.
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