SOLUTION: How do you solve -16+0.2(10)^x=35

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Question 74757: How do you solve -16+0.2(10)^x=35
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
-16%2B0.2%2810%29%5Ex=35
cross%28-16%2B16%29%2B0.2%2810%29%5Ex=35%2B16Add 16 to both sides
0.2%2810%29%5Ex=35%2B16
cross%280.2%2F0.2%29%2810%29%5Ex=51%2F0.2Divide both sides by 0.2
log%2810%5Ex%29=log%28255%29Take the log of both sides, this undoes the base 10 to the unknown exponent
x=log%28255%29
x=2.40654


Check:
-16%2B0.2%2810%29%5Ex=35Plug in x=2.40654
-16%2B0.2%2810%29%5E%282.40654%29=35
-16%2B0.2%2810%29%5E%282.40654%29=35
-16%2B0.2%28254.99989%29=35
-16%2B50.99997=35
34.99997=35These two are really close to being equal. They would be if not for decimal roundoff error, so it works.