Someone answer please, its a test. will give brainliest to the fastest.

If logb2=x and logb3=y, evaluate the following in terms of x and y:

Alja [10]

$log_b{162} = x + 4y\\\\log_b324 = 2x+4y\\\\log_b\frac{8}{9} = 3x-2y\\\\\frac{log_b27}{log_b16} = 3y-4x$

Solution:

Given that,

$log_b2 = x\\\\log_b3 = y --------(i)$

Use the following log rules

Rule 1: $log_b(ac) = log_ba + log_bc$

Rule 2: $log_b\frac{a}{c} = log_ba - log_bc$

Rule 3: $log_ba^c = clog_ba$

$a) log_b{162}$

Break 162 down to primes:

$162 = 2^1 \times 3^4$

$log_b{162} =log_b 2^1. 3^4\\\\By\ rule\ 1\\\\ log_b{162} = log_b 2^1 +log_b 3^4\\\\By\ rule\ 3\\\\1log_b2 + 4log_b3\\\\1x+4y\\\\x+4y$

Thus we get,

$log_b162 = x + 4y$

Break 324 down to primes:

$324 = 2^2 \times 3^4$

$log_b324 = log_b 2^2.3^4\\\\By\ rule\ 1\\\\log_b324 = log_b2^2 + log_b3^4\\\\By\ rule\ 3\\\\log_b324 = 2log_b2 + 4log_b3\\\\From\ (i)\\\\log_b324 = 2x + 4y$

By rule 2

$log_b\frac{8}{9} = log_b8 - log_b9\\\\log_b\frac{8}{9} = log_b 2^3 - log_b3^2\\\\By\ rule\ 3\\\\log_b\frac{8}{9} = 3 log_b2 - 2log_b3\\\\From\ (i)\\\\log_b\frac{8}{9} = 3x - 2y$

By rule 2

$\frac{log_b27}{log_b16} = log_b27 - log_b16\\\\ \frac{log_b27}{log_b16} = log_b3^3 - log_b2^4\\\\By\ rule\ 2\\\\ \frac{log_b27}{log_b16} = 3log_b3 - 4log_b2 \\\\From\ (i)\\\\\frac{log_b27}{log_b16} = 3y - 4x$

Thus the given are evaluated in terms of x and y

3 0

3 years ago

An electric utility company determines the monthly bill for a residential customer by adding an energy charge of 7.32 cents per

Sedaia [141]

Answer:

$y(x) = 0.0732x + 17.32$

Step-by-step explanation:

The equation for the monthly charge has the following format

$y(x) = ax + b$

In which y(x) is the cost in function of the number of kilowatt-hours used(x), a is the price of each killowatt hour and b is the fixed(base) charge.

Base charge of $17.32 per month.

This means that $b = 17.32$

charge of 7.32 cents per kilowatt-hour

Our answer is in dollars. Each dollar is 100 cents. So 7.32 cents is $a = 0.0732$

Write an equation for the monthly charge y in terms of x, the number of kilowatt-hours used.

$y(x) = ax + b$

$y(x) = 0.0732x + 17.32$

6 0

3 years ago

10th grade Geo | What does JK equal?

ladessa [460]

Answer:

16

Step-by-step explanation:

6x-7=2x+3 Cause point M is the midpoint, so JM and MK have to be equal.

4x=10

x=2.5

JM=15-7=8 and MK=5+3=8

8+8=16

4 0

3 years ago

Can someone help me with this

gulaghasi [49]

Answer:

Y is 90 degrees.

Step-by-step explanation:

This is an equalterial triangle which means all of the angles are the same. The angle for the upper part of the triangle is 60 as well. We can do 2x=60 because they add up to the angle which is 60. This gives us x=30. If x=30 and the other angle is 60, then the other angle has to be 90 because all triangle has an angle sum of 180. So 30 +60 + 90= 180. Hope this helps!

4 0

4 years ago

Read 2 more answers

The ratio of boys to girls in the classroom is 12:25 if there are 120boys how many girls are there

Ann [662]

Call x is the number of girls in the classroom.
12/120 = 25/x
x = 120*25/12
x=250
Answer 250 girsl

8 0

3 years ago

Read 2 more answers