SOLUTION: Solve for the unknown: 60[log(3+z)+2log(2)]-15=85 Help!

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: Solve for the unknown: 60[log(3+z)+2log(2)]-15=85 Help!      Log On


   



Question 684415: Solve for the unknown:
60[log(3+z)+2log(2)]-15=85
Help!

Answer by MathTherapy(10555) About Me  (Show Source):
You can put this solution on YOUR website!

Solve for the unknown:
60[log(3+z)+2log(2)]-15=85
Help!

60%28log+%28%283+%2B+z%29%29+%2B+2log+2%29+-+15+=+85

60%28log+%28%283+%2B+z%29%29+%2B+log+2%5E2%29+-+15+=+85

60%28log+%28%283+%2B+z%29%29+%2A+4%29+-+15+=+85

60%28log+%2812+%2B+4z%29%29+-+15+=+85

60%28log+%2812+%2B+4z%29%29+=+85+%2B+15

60%28log+%2812+%2B+4z%29%29+=+100

log+%2812+%2B+4z%29+=+100%2F60

log+%2812+%2B+4z%29+=+5%2F3

12+%2B+4z+=+10%5E%285%2F3%29

4z+=+-+12+%2B+10%5E%285%2F3%29

4z = 34.41589

z = 34.41589%2F4, or 8.603972 ≈ highlight_green%288.6%29

You can do the check!!

Send comments and “thank-yous” to “D” at MathMadEzy@aol.com