Find all values of $s$ such that $(s + 4)(s - 3) ≤ 0$. Give your answer as an interval.
Find all values of $x$ that satisfy $x(x+7.5) > 38.5$. Give your answer as an interval.
Find all values of $t$ such that $8t^2 ≤ 3-10t$.
Perhaps these graphs will help:
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