What is the answer to log_{x}(x+20)=2 ?

The answer to log_{x}(x+20)=2 is x=5

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

log_{x}(x+20)=2

lo g_{x} (x + 20) = 2

x = 5

Solution steps

lo g_{x} (x + 20) = 2

Apply log rules

\frac{ln ( x + 20 )}{ln ( x )} = 2

Multiply both sides by

ln (x)

\frac{ln ( x + 20 )}{ln ( x )} ln (x) = 2 ln (x)

Simplify

ln (x + 20) = 2 ln (x)

Apply log rules

x + 20 = x^{2}

Solve

x + 20 = x^{2} : x = 5, x = - 4

x = 5, x = - 4

Verify Solutions:

x = 5

True

, x = - 4

False

The solution is

x = 5

lo g_{4} (x - 95) = lo g_{4} (x - 5) + 2

lo g_{10} (100 x) = 3

lo g_{2} (x + 4) = 1 + lo g_{2} (x + 3)

lo g_{2} (4 x) + 2 lo g_{2} (5) = 3

4 ln (- x) = 18