Solve for u: 1.5u + 8.0 = 3.5

To solve for "u", you need to isolate/get the variable "u" by itself in the equation:

1.5u + 8.0 = 3.5    Subtract 8.0 on both sides

1.5u + 8.0 - 8.0 = 3.5 - 8.0

1.5u = -4.5      Divide 1.5 on both sides to get "u" by itself

u = -3

PROOF

1.5u + 8.0 = 3.5     Plug in -3 for "u"

1.5(-3) + 8.0 = 3.5

-4.5 + 8.0 = 3.5

3.5 = 3.5

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)

4.08%

step-by-step explanation: