A y = 19.8x + 1080.2

b
y = 19.8x + 1100

c
y = 16.8x + 1080.2

d
y = 16.8x + 1100

step-by-step explanation:

the original amount doesn't ''re just looking for the time it takes for 1/2 of the substance to we have

(1/2) =)     take the ln   of both sides

ln (1/2)   = )   and we can write

ln(1/2) = ) lne     and lne   = 1     so we have

ln(1/2) = -.1092t     divide both sides by -.1092

t = ln(1/2)/-.1092 = about 6.347 days = about 6.3 days (rounded)

-2x + 7 = 7

subtract 7 from both sides.

-2x = 0

divide both sides by -2.

x = 0

answer: b

step-by-step explanation: im sorry bro bro but thats not a eqation the human mind can answer and plus im a devil

answer: (3,11) is your answer.