Question
Solve the equation
x=72log5(2)−6
Alternative Form
x≈−0.734092
Evaluate
log10(5)×(x×8)−log10(5)×(x−8)=2
Remove the parentheses
log10(5)×x×8−log10(5)×(x−8)=2
Use the commutative property to reorder the terms
8log10(5)×x−log10(5)×(x−8)=2
Move the expression to the left side
8log10(5)×x−log10(5)×(x−8)−2=0
Calculate
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Evaluate
8log10(5)×x−log10(5)×(x−8)−2
Expand the expression
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Calculate
−log10(5)×(x−8)
Apply the distributive property
−log10(5)×x−(−log10(5)×8)
Multiply the numbers
−log10(5)×x−(−8log10(5))
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
−log10(5)×x+8log10(5)
8log10(5)×x−log10(5)×x+8log10(5)−2
Subtract the terms
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Evaluate
8log10(5)×x−log10(5)×x
Collect like terms by calculating the sum or difference of their coefficients
(8log10(5)−log10(5))x
Subtract the numbers
7log10(5)×x
7log10(5)×x+8log10(5)−2
7log10(5)×x+8log10(5)−2=0
Move the constant to the right-hand side and change its sign
7log10(5)×x=0−(8log10(5)−2)
Subtract the terms
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Evaluate
0−(8log10(5)−2)
If a negative sign or a subtraction symbol appears outside parentheses, remove the parentheses and change the sign of every term within the parentheses
0−8log10(5)+2
Removing 0 doesn't change the value,so remove it from the expression
−8log10(5)+2
7log10(5)×x=−8log10(5)+2
Divide both sides
7log10(5)7log10(5)×x=7log10(5)−8log10(5)+2
Divide the numbers
x=7log10(5)−8log10(5)+2
Divide the numbers
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Evaluate
7log10(5)−8log10(5)+2
Rewrite in terms of common logarithms
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Evaluate the logarithm
−8log10(5)+2
Calculate
log10(5−8)+2
Rewrite in terms of common logarithms
log10(5−8)+log10(100)
Use the logarithm product rule
log10(5−8×100)
Evaluate the logarithm
log10(100×5−8)
7log10(5)log10(100×5−8)
Rewrite in terms of common logarithms
log10(57)log10(100×5−8)
Use the logarithm base change rule
log57(100×5−8)
x=log57(100×5−8)
Solution
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Evaluate
log57(100×5−8)
Rewrite the expression
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Evaluate
100×5−8
Express with a positive exponent using a−n=an1
100×581
Rewrite the expression
25×4×581
Rewrite the expression
52×4×581
Reduce the numbers
4×561
Multiply the numbers
564
log57(564)
Use loga(yx)=loga(x)−loga(y) to transform the expression
log57(4)−log57(56)
Simplify the expression
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Evaluate
log57(4)
Write the number in exponential form with the base of 2
log57(22)
Use logambn=mnlogab to simplify the expression
72log5(2)
72log5(2)−log57(56)
Use logaman=mn to simplify the expression
72log5(2)−76
Rewrite the expression
72log5(2)−76
Write all numerators above the common denominator
72log5(2)−6
x=72log5(2)−6
Alternative Form
x≈−0.734092
Show Solution
