What is the quadratic regression equation?
Use the Desmos graphing calculator and round each coefficient in the equation to
the nearest thousandth.
Enter your answer in the box. Do not use spaces. Use y instead of Y and use shift 6
^ for exponents (x² = x^2).

y=-0.078x^2+8.407x+-92.892

Step-by-step explanation:

but your x and y in desmo than go under the table do y1=ax^2 then under the 2 put a 1 than +bx1+c than you round your a b and c to the nearest thousandth than after that add a b and c then after you get your answer than but x^2 behind a than x behind b then nothing behind c hope this works for you

nope.   happens to me as well.

-aparri

ending amount = beginning amount / (2^n)

where "n" = number of half-lives (or elapsed time / half-life)

ending amount = 50 mg / (2 ^10 / 5.3)

ending amount = 50 mg / (2 ^ 1.8867924528)

ending amount = 50 m / 3.6981210597

ending amount = 13.5203794557 mg

or about 13.5 mg remain

source: