"Complementary" angles sum to 90°.
Since we are using minutes as well...
80°+d°+25'+m'=90° subtract 80° from both sides
d°+25'+m'=10° subtract 25' from both sides
d°+m'=9°+60'-25'
d°+m'=9°+35'
9°35'
You’d have to solve your equations!
they’d be the same when x=-56
and when x=-56 they’d BOTH equal -27
240 days is 4 times the half-life, which means that a sample of 1000 mg will decay to

after 240 days.
The correct answer is 35.2 because when you arrange them in order from least to greatest, the middle is 35.2