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3 years ago

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Find the domain of f(x)=x-9/x squared-81

1 answer:

vagabundo [1.1K]3 years ago

7 0

$f(x)=\dfrac{x-9}{x^2-81}\\\\\text{The domain:}\\\\x^2-81\neq0\qquad\text{add 81 to both sides}\\\\x^2\neq81\to x\neq\pm\sqrt{81}\\\\x\neq-9\ \wedge\ x\neq9\\\\Answer:\ \boxed{\text{All real numbers except -9 and 9}}\to\boxed{x\in\mathbb{R}-\{-9,\ 9\}}$

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Help with this one? Please

netineya [11]

Answer:

x = 40

Step-by-step explanation:

The figure shows two similar triangles. Thus, the side lengths of similar triangles are proportional to each other. Therefore:

$\frac{24}{24 - 15} = \frac{x}{x - 25}$

$\frac{24}{9} = \frac{x}{x - 25}$

Cross multiply

$24(x - 25) = 9(x)$

$24x - 600 = 9x$

Subtract 24x from each side

$- 600 = 9x - 24x$

$- 600 = -15x$

Divide both sides by -15

$40 = x$

x = 40

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2 years ago

For each system of equations, drag the true statement about its solution set to the box

iVinArrow [24]

<h2 /><h2> $1$ </h2>

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2 years ago

Help with math please???

Tresset [83]

Okay, let's see...

The problem is asking for a linear equation most likely in the form of y=mx+b

y is another way to say f(x)

<em>m = slope </em>

<em>b = y intercept </em>

Let's start with the y intercept first.

Y intercept means ' When does the line touch (intercept) the y axis.

In this case, if you look at the graph, the line <em>touches </em>the y axis at -1.

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Lets use <em>(0,-1)</em> and <em>(-6,4) </em>

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2 years ago

Ms. Tyson has a part time job selling cars. She earns a commission of 0.6% on all her sales. If her sales for last week was $281

In-s [12.5K]

Based on the information given her commission check is $1,689.8.

Using this formula

Commission check=Commission earned× Sales

Where:

Commission earned=0.6% or 0.006

Sales=$281,634

Let plug in the formula

Commission check= 0.006×$281,634

Commission check=$1,689.8

Inconclusion her commission check is $1,689.8.

Learn more here:brainly.com/question/24030244

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2 years ago

Write the equation of the line that passes through the points (0,8) and (-1, –4).

andrey2020 [161]

Answer:

Step-by-step explanation

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Now plug your m value and (x1, y1) into point-slope form:

$y - 8 = 12(x-0)\\reduce\\y=12x+8$

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2 years ago