Sequence & Series
Please show all work, and try to explain a bit I've hit a brick wall with these questions.
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in number 10 how did 5a + 10d become 15a + 30d and why?

also you you didn't show all the work

you jumped over alot of steps could you go back and provide all the work like for example how to get the a term

Hi, My bad  I assumed the systems of equations part was intuitive but I guess not. I went back in and added some explanation for the steps, plus a general explanation of systems of equations at the beginning to hopefully make it a bit more intuitive. Please see the new file attached. Thanks.
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