Suppose you know the slope of a linear relationship and one of the points that it's graph passes through. how can you determine if the relationship is proportional or nonproportional

Bismuth-210 is an isotope that radioactively decays by about 13% each day, meaning 13% of the remaining bismuth-210 transforms into another atom (polonium-210 in this case) each day. if you begin with 233 mg of bismuth-210, how much remains after 8 days?

What is the quadric regression equation that fits these data

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