not sure how to do this one.
solving for a
To solve for something means to isolate that thing on the left side of the equation.
d = (1/2) a t^2
(1/2) a t^2 = d
Multiply by 2, divide by t^2,
(2/t^2)*(1/2) a t^2 = (2/t^2) d
Clear fractions and reduce,
a = 2 d/t^2
and the equation is solved for a.
You really need to learn algebra!
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