SOLUTION: How can I solve this exponential equation alegbracally? 225[(1+0.05)^x/0.05]=300000

Algebra ->  Logarithm Solvers, Trainers and Word Problems -> SOLUTION: How can I solve this exponential equation alegbracally? 225[(1+0.05)^x/0.05]=300000      Log On


   

Question 859252: How can I solve this exponential equation alegbracally? 225[(1+0.05)^x/0.05]=300000
Found 2 solutions by josmiceli, edjones:
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
+225+=+%28+1+%2B+.05+%29%5E%28+x%2F.05+%29+%29+=+300000+
Divide both sides by +225+
++%28+1+%2B+.05+%29%5E%28+x%2F.05+%29+%29+=+1333.333+
Take the log of both sides
+%28+x%2F.05+%29%2Alog%28+1.05+%29+=+log%28+1333.333+%29+
+.0211893%2A+%28+x%2F.05+%29+=+3.12494+
+x%2F.05+=+147.4772+
+x+=+7.37386+
--------------------
check:
+x%2F.05+=+147.4772+
+1.05%5E147.4772+=+1333.3326+
+225%2A1333.3326+=+299999.835+
+300000+-+299999.835+=+.165+
close enough

Answer by edjones(8007) About Me  (Show Source):
You can put this solution on YOUR website!
225[(1+0.05)^x/0.05]=300000
4500*1.05^x=30000 multiply each side by 20.
1.05^x=200/3
log(1.05)1.05^x=x
x=log(1.05)200/3
=ln(200/3)/ln(1.05)
=~ 4.1997/.04879
=~ 86.0769
.
Ed