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How Do I Solve The Given Logarithmic Equation

How would you solve this logarithmic equation?

I assume you meant to write log (subscript)b 3 = y.

For this problem, you just need to know the log rules:
log (a) + log (b) = log (ab)
log (a) - log (b) = log (a/b)

18 = 3*3*2, so
log(b) 18 = log (b) (2*3*3) = log (b) 2 + log (b) 3 + log (b) 3
= x + 2y

9/16 = (3*3)/(2*2*2*2), so
log(b)(9/16) = log(b) 3 + log(b) 3 - log(b) 2 - log(b) 2 - log(b) 2 - log(b) 2
= 2y/4x = y/2x

Hope that helps!

How do I solve the logarithmic equation.

I think this is what you mean (where I am using log7 to mean log to the base 7). Just read your additional comments so here is my new answer:

log7(x) + log7 (x - 48) = 2

Use the fact that:
log7(a) + log7(b) = log(ab)

log7[x(x - 48)] = 2

Now use the fact that:
log7(a) = b can be changed to a = 7^b

x(x - 48) = 7^2 = 49
x^2 - 48x - 49 = 0
(x - 49)(x + 1) = 0
The answers are: x = 49 and x = -1

However x = -1 is not a good solution since x > 48 based on the second term of the original equation. Since we are taking log7 of (x - 48) x must be greater than 48 to get a valid log.

The answer is x = 49

Check:
log7(49) + log7(49 - 48) = log7(49) + log7(1) = 2 + 0 = 2
And the answer given above is correct

Explain how to solve exponential and logarithmic equations by graphing.?

graph plotting is a very good method to find solutions but u need to hve good graph plotting technique. first plot a good graph and find the points where figures are intersecting each other this point will be called a soution. for logarithm u need to first find its domain and then see where its nature changes like increasing or decreasing

4.Solve the given equation. (a). In x = 0.35 X=? (b). log x = 0.35 X=?

a) x = e^0.35

b) x = 10^0.35

Solve the logarithmic equation for x. (Enter your answers as a comma-separated list.) log2(x + 9) − log2(x − 9) = 3?

log2(x + 9) − log2(x − 9) = 3 : x ≠ -9, 9
log2[(x+9)/(x-9)] = 3
(x+9)/(x-9) = 8
x+9 = 8x - 72
x = 8x-81
-7x = -81
x = 81/7

TI-89 Titanium Solving Logarithmic Equations for x?

Do you know that "change of base" formula for logarithms?
Most calculators do only base 10 (LOG button) and base e (LN button) logarithms.
To do any other base, say "B", enter Log(x)/Log(B).
For example the base 3 logarithm of 81 is 4: Log(81)/Log(3) = 4.

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The standard graphing calculator equation solving procedure is:
Graph both sides of the equation and use the "intersection" feature:

On most calculators: Press "Y=" (diamond-f1 on a TI-89) and enter:
Y1 = Log(x+1)/Log(3) - Log(x-2)/Log(5)
Y2 = 2
Press the "Graph" button (diamond-f3 on a TI-89)
and then use the "intersection" function ("F5" then "5" on a TI-89; "Calc" button on other TI's; and "G-Solv" on most Casio's). Follow the directions on screen, each brand is a little different.

WARNING! This equation has more than one solution. It is very easy to overlook the other solution if you only look at the graph with the standard window.

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Here is another cute way to solve that equation which works both on graphing and many non-graphing calculators:

Solve for the one of the "X", perhaps first "x".
( Put both sides in the exponent of "5" to eliminate the base 5 logarithm,
( Multiply by (x-2), then raise both sides to the power of Log(3)/Log(5) and subtract 1:
x = (25(x-2)) ^ (Log(3)/Log(5)) -1

On the calculator, enter a guess, perhaps "10", and press enter.
Then type:

     (25*(ANS-2)) ^ (LOG(3)/LOG(5)) - 1

and press "enter" again and again and again until the answer stops changing.
{It might take awhile. "10" is not a good guess!}

The other solution can be found by solving for the other "x" value:
x = ((x+1)/9) ^ (Log(5)/Log(3)) + 2

Find the solutions to the logarithmic equation: log2(x^2-2x-76)=2?

A logarithm is nothing more than an exponent. The expression on the left is nothing more than the exponent you need to raise 2 to produce the quantity in ( ). If you think of both sides as exponents to the base 2, you get from the properties of logarithms, the equation

x^2 - 2x - 76 = 4.

Now, solve the equation x ^2 - 2x - 80 = 0. This factors as
(x - 10)(x + 8) = 0.

Solving, you get x = -8, 10. However, you must make sure that the expression in ( ) is always > 0, Only - 8 satisfies that condition.

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