Nick starts with 20 milligrams of a radioactive substance. The amount of the substance decreases by 1/2 each week for a number of weeks, w. He writes the expression 20 1/2 to find the amount of the radioactive substance remaining after w weeks.

How do you use the elimination method for this question? explain, because i really want to understand!

Jabari is power washing houses for a summer job. for every job, he charges an initial fee plus $30 for each hour of work. his total fee for a 4 -hour job, for instance, is $170 . jabari's total fee,f, for a single job is a function of the number,t, of hours it takes him to complete the job. write the function's formula.

The number of fish in a lake can be modeled by the exponential regression equation y=14.08 x 2.08^x where x represents the year