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3 votes
2^x+5 = 3^1-x use logarithms to solve the exponential equation. round answer to 3 decimal places.

User Varkal
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2 Answers

1 vote
2^x+5 = 3^1-x
take log on both sides
(x+5)log2=(1-x)log3
0.3010(x+5) = (1-x)0.4771
0.3010x + 1.5050 = 0.4771 - 0.4771x
0.7781x= -1.0279
x=-1.320

User Wiggy
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7.8k points
4 votes

2^(x+5)=3^(1-x)\ \ \ \ \ /log_2()\\\\log_22^(x+5)=log_23^(1-x)\\\\x+5=(1-x)log_23\\\\x+5=log_23-xlog_23\\\\x+xlog_23=log_23-5\\\\x(1+log_23)=log_23-5\ \ \ \ /:(1+log_23)


x=(log_23-5)/(1+log_23)\\-------------\\log_23\approx1.5849625\\----------------\\x\approx(1.5849625-5)/(1+1.5849625)\approx-1.321
User Kubilay
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