Expand the expression to yield a trinomial of the form ax² + bx + c. (2x + 3)²

Gwar [14]

Answer:

$x = 3$ $and$ $x = -3$

Step-by-step explanation:

In this problem, we are substituting for x.

Let us take a look at our given answers.

x = -13 and x = -3 would not work because the numbers would not add up to -5. Since we have the positive brackets (or whatever you call them.) surrounding the x variable, that means that all numbers that are plugged into x will be positive.

-13 will be turned into 13,

13 - 8 $\neq$ -5

So that is wrong.

x = 3 and x = 3 would work because plugging it in, all outcomes from the two numbers would be negative.

3 - 8 = -5

$|-3|$ - 8 = -5

True.

The third one won't work because of the same reasons as the first one.

Then, the last one would not work well because, there is a solution.

4 0

3 years ago

Find the equation of the line which passes through the point (7,2) and is perpendicular to y=5x-2

MariettaO [177]

Answer:

$\displaystyle y=-\frac{1}{5}x+\frac{17}{5}$

Step-by-step explanation:

Equation of a line

A line can be represented by an equation of the form

$y=mx+b$

Where x is the independent variable, m is the slope of the line, b is the y-intercept and y is the dependent variable.

We need to find the equation of the line passing through the point (7,2) and is perpendicular to the line y=5x-2.

Two lines with slopes m1 and m2 are perpendicular if:

$m_1.m_2=-1$

The given line has a slope m1=5, thus the slope of our required line is:

$\displaystyle m_2=-\frac{1}{m_1}=-\frac{1}{5}$

The equation of the line now can be expressed as:

$\displaystyle y=-\frac{1}{5}x+b$

We need to find the value of b, which can be done by using the point (7,2):

$\displaystyle 2=-\frac{1}{5}*7+b$

Operating:

$\displaystyle 2=-\frac{7}{5}+b$

Multiplying by 5:

$10=-7+5b$

Operating:

$10+7=5b$

Solving for b:

$\displaystyle b=\frac{17}{5}$

The equation of the line is:

$\boxed{\displaystyle y=-\frac{1}{5}x+\frac{17}{5}}$

7 0

3 years ago

which of the functions have a range of real numbers greater than or equal to 1 or less than or equal to-1

lilavasa [31]

The question is incomplete. Here is the complete question:

Which of the functions have a range of all real numbers greater than or equal to 1 or less than or equal to -1? check all that apply.

A. $y=\sec x$

B. $y= \tan x$

C. $y= \cot x$

D. $y= \csc x$

Answer:

A. $y=\sec x$

D. $y=\csc x$

Step-by-step explanation:

Given:

The range is greater than or equal to 1 or less than or equal to -1.

The given choices are:

Choice A: $y=\sec x$

We know that, the $\sec x=\frac{1}{\cos x}$

The range of $\cos x$ is from -1 to 1 given as [-1, 1]. So,

$|\cos x|\leq 1\\\textrm{Taking reciprocal, the inequality sign changes}\\\frac{1}{|\cos x|}\geq 1\\|\sec x|\geq 1$

Therefore, on removing the absolute sign, we rewrite the secant function as:

$\sec x\leq -1\ or\ \sec x\geq 1\\$

Therefore, the range of $y=\sec x$ is all real numbers greater than or equal to 1 or less than or equal to-1.

Choice B: $y= \tan x$

We know that, the range of tangent function is all real numbers. So, choice B is incorrect.

Choice C: $y= \cot x$

We know that, the range of cotangent function is all real numbers. So, choice C is incorrect.

Choice D: $y=\csc x$

We know that, the $\csc x=\frac{1}{\sin x}$

The range of $\sin x$ is from -1 to 1 given as [-1, 1]. So,

$|\sin x|\leq 1\\\textrm{Taking reciprocal, the inequality sign changes}\\\frac{1}{|\sin x|}\geq 1\\|\csc x|\geq 1$

Therefore, on removing the absolute sign, we rewrite the cosecant function as:

$\csc x\leq -1\ or\ \csc x\geq 1\\$

Therefore, the range of $y=\csc x$ is all real numbers greater than or equal to 1 or less than or equal to-1.

6 0

3 years ago

Here is a uniform probability distribution.

Darya [45]

a) $P(4\le X\le6)=\dfrac25$ because it is equal to the area of the shaded region between X=4 and X=6, and the probability that X falls within some interval is given by the area under the PDF.

b) $a=3$ because the shaded region is a rectangle of height 1/5 (by virtue of X following a uniform distribution over the interval [2, 7], which has length 5).

4 0

3 years ago

Which are perfect trinomials?

Natalija [7]

Answer:

A perfect square trinomial is the square of a binomial. It follows a pattern when it is factored, so that the first and last terms are perfect squares of monomials and the middle term is twice their product

Step-by-step explanation:

5 0

3 years ago