Element X decays radioactively with a half life of 6 minutes. If there are 900 grams of Element X, how long, to the nearest tenth of a minute, would it take the element to decay to 121 grams?

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18

idk

step-by-step explanation:

slope is 35 and 20 miles is the y-intercept.

step-by-step explanation:

i believe your answer is 99.7% of 7-year-old children are between 46.6 inches and 49.5 inches tall.