the half-life of a certain medicine is 6 hours. if 4000 mg is the initial amount prescribed, then how much medicine remains after 18 hours?

X/y + 4y/x divided by x/y - 2y/x explain as in depth as you can how you simplfied the fractions. i don't know where to start on this : /

To prove that angle def = angle dgf by sas, what additional information is needed? def congruent to dgf dfe congruent to dfg de congruent to dg dg congruent to gf

What is the absolute value of -100000000000000?