I didn't learn this. Sorry
Answer:
x= -5
Step-by-step explanation:
3x+3=2x-2
3x-2x=-3-2
x=-5
Answer:
Option A. 10 years
Step-by-step explanation:
we know that
Half-life
is the amount of time required for a quantity to fall to half its value as measured at the beginning of the time period.
In this problem
of a radioactive isotope is 10 years, which means that after 10 years half of the sample would have decayed and half would be left as it is.
After 10 years ( first half life) 5/2 = 2.5 g decays and 2.5 g remains left