The perimeter, P, of a rectangle is the sum of twice the length and twice the width. P = 2l+ 2w units
P = 2(l+w) units
P = 2(x+3) units
P = 2(5)+2(9) units
P = 4 x units

see attached

step-by-step explanation:

given the function as;

write the equation replacing f(x) with y

form   and fill a table containing values of y with corresponding values of x

you can take a range for   values of x as -3≤x≤3

solving for x=-3

for x=-2

repeat the same procedure to get the values of y for the remaining ,x=-1 to x=3

plot the values of y against values   of x and obtain the following graph

step-by-step explanation:

a'(12.5,11.25)

slope=(y1-y2)/(x1-x2)

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: