Rational expressions always contain logarithms. 1) Always true 2) Never true 3) Sometimes true

LenKa [72]

5x - 3y = 9
5x = 9 + 3y
5x - 9 = 3y
( 5x - 9 ) / 3 = y
y = ( 5 / 3x ) - ( 9 / 3 ) ( I just split the common denominator to individual parts )
y = 5 / 3x - 3

8 0

3 years ago

Please help me with this question. Algebra 2 is hard!!

trapecia [35]

Answer:

domain: {x ∈ ℝ : x ≤ 5}
range: {y ∈ ℝ : y ≤ -1}

Step-by-step explanation:

Domain

The domain of a function is the set of x values for which the function is defined. Here, the domain is limited by the values of x that make the square root defined. That is, the expression under the radical cannot be negative:

-3x +15 ≥ 0

15 ≥ 3x . . . . . . add 3x

5 ≥ x . . . . . . . . divide by 3

x ≤ 5 . . . . . . . . put x on the left (swap sides)

The rest of the notation in the domain expression simply says x is a real number.

domain: {x ∈ ℝ : x ≤ 5} . . . . . . matches the first choice

__

Range

The range of a function is the set of values that f(x) can have. We know the square root can be zero or any positive number. When it is zero, f(x) = -1.

When it is a positive number, that value is multiplied by -4 and added to -1, so f(x) is a number more negative than -1. Then the range of the function is all numbers -1 and below:

range: {y ∈ ℝ : y ≤ -1} . . . . . . matches the last choice

_____

Comment on domain/range problems

When working domain and range problems, it works well to have a good understanding of the domain and range limitations of the functions we usually work with: polynomials, square root, logarithm, trig functions, exponential functions. Domain and range problems generally involve combinations of these or ratios of combinations of these.

3 0

3 years ago

Am I correct?? I did not count the last square unit at the vertices of each corner.

mariarad [96]

The answer would actually be a 110 units because the bottom left corner had 20 units and the bigger square had 90.

3 0

3 years ago

There are 15 juniors and 10 seniors in a class. What is the probability that if two students are selected at random that they ar

Brums [2.3K]

Answer:

2/25?

Step-by-step explanation:

3 0

3 years ago

The length of the hypotenuse of a right triangle is 24. If the length of one leg is 8, what is approximate length of the other l

Verdich [7]

Something that a right triangle is characterised by is the fact that we may use Pythagoras' theorem to find the length of any one of its sides, given that we know the length of the other two sides. Here, we know the length of the hypotenuse and one other side, therefor we can easily use the theorem to solve for the remaining side.

Now, Pythagoras' Theorem is defined as follows:

c^2 = a^2 + b^2, where c is the length of the hypotenuse and a and b are the lengths of the other two sides.

Given that we know that c = 24 and a = 8, we can find b by substituting c and a into the formula we defined above:

c^2 = a^2 + b^2

24^2 = 8^2 + b^2 (Substitute c = 24 and a = 8)

b^2 = 24^2 - 8^2 (Subtract 8^2 from both sides)

b = √(24^2 - 8^2) (Take the square root of both sides)

b = √512 (Evaluate 24^2 - 8^2)

b = 16√2 (Simplify √512)

= 22.627 (to three decimal places)

I wasn't sure about whether by 'approximate length' you meant for the length to be rounded to a certain number of decimal places or whether you were meant to do more of an estimate based on your knowledge of surds and powers. If you need any more clarification however don't hesitate to comment below.

4 0

3 years ago