element x is a radioactive isotope such that every four years, its mass decreases by half. given that the initial mass of a sample of element X is 300 grams, how long would it be until the mass of the sample reached 90 grams

2? if not the correct answer you might need to provide more information

step-by-step explanation:

the answer is (-8,-5)

step-by-step explanation:

the endpoint to midpoint is half the length. the length is (-2,-1) so when you are at the midpoint just add it to it to find your answer -6+(-2)= -8 and -4+(-1)=-5 so (-8,-5)