10/13 = 8 - 2z/52 Thats the question. Im dyin for help. :)

z = 188

Step-by-step explanation:

1. 10/13 = 8 - 2z/52 (simplify - 2z/52)

10/13 = 8 (- 1/26)*z

2. 10/13 = (- 1/26)*z + 8 (flip for ease in solving)

(- 1/26)*z + 8 = 10/13

3. (- 1/26)*z + 8 = 10/13 (inverse: subtract 8 from each side to isolate variable z)

(- 1/26)*z = 10/13 - (8*13)/(1*13)  (common denominator needed for add/subtract)

(- 1/26)*z = - 94/13 (simplify)

4. (- 1/26)*z = - 94/13 (inverse: multiply both sides by -26/1 to isolate variable z)

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)