Answer
$-3t^{2}+21t-22$
Work Step by Step
Expand the brackets, be mindful of the negative sign:
$=15t-20-t^{2}-2-2t^{2}+6t$
Collect the like terms:
$=(-1-2)t^{2}+(15+6)t+(-20-2)$
$=-3t^{2}+21t-22$
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