I am new to this. I am trying to teach myself algebra and physics. I am trying to understand the last part of this under
relating the objects. All circled variables are unknowns. More specifically part 3 and 4 especially 4, using a quadratic formula to figure out the unknown for t (
time).
1. Can you provide some clarity how the author found the unknowns when there are multiple unknowns in each equation? I have read there are ways to solve for two unknowns, but in this case it's a little foggy to me.
2. When do I know a situation calls for the use of the quadratic equation? I had no idea to use that here.
t^2-18t-20=0
I would not have known what numbers and variables especially
t^2 to insert into quadratic equation.
Thanks.
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