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4 years ago

Use the unit circle to find cos (-270°)

Mathematics

1 answer:

daser333 [38]4 years ago

7 0

Answer:

$\cos (-270\degree)=0$ .

Step-by-step explanation:

We want to find the value of $\cos (-270\degree)$ .

Note that;

$\cos (-\theta)=\cos (\theta)$

This implies that;

$\cos (-270\degree)=\cos (270 \degree)$

Also 270 degrees is a quadrantal angle.

On the unit circle, $\cos (270\degree)$ is the x-coordinate of the point $(0,-1)$

Hence, $\cos (-270\degree)=0$ .

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34. For the following exercises, given each set of information, find a linear equation satisfying the conditions, if possible.

skad [1K]

Answer:

The linear equation for the line which passes through the points given as (-1,4) and (5,2), is written in the point-slope form as $y=\frac{1}{3} x-\frac{13}{3}$ .

Step-by-step explanation:

A condition is given that a line passes through the points whose coordinates are (-1,4) and (5,2).

It is asked to find the linear equation which satisfies the given condition.

Step 1 of 3

Determine the slope of the line.

The points through which the line passes are given as (-1,4) and (5,2). Next, the formula for the slope is given as,

$m=\frac{y_{2}-y_{1}}{x_{2}-x_{1}}$

Substitute 2&4 for $y_{2}$ and $y_{1}$ respectively, and $5 \&-1$ for $x_{2}$ and $x_{1}$ respectively in the above formula. Then simplify to get the slope as follows,

$m=\frac{2-4}{5-(-1)}$\\ $m=\frac{-2}{6}$\\ $m=-\frac{1}{3}$$

Step 2 of 3

Write the linear equation in point-slope form.

A linear equation in point slope form is given as,

$y-y_{1}=m\left(x-x_{1}\right)$

Substitute $-\frac{1}{3}$ for m,-1 for $x_{1}$ , and 4 for $y_{1}$ in the above equation and simplify using the distributive property as follows,

$y-4=-\frac{1}{3}(x-(-1))$\\ $y-4=-\frac{1}{3}(x+1)$\\ $y-4=-\frac{1}{3} x-\frac{1}{3}$$

Step 3 of 3

Simplify the equation further.

Add 4 on each side of the equation $y-4=\frac{1}{3} x-\frac{1}{3}$ , and simplify as follows,

$y-4+4=\frac{1}{3} x-\frac{1}{3}+4$\\ $y=\frac{1}{3} x-\frac{1+12}{3}$\\ $y=\frac{1}{3} x-\frac{13}{3}$$

This is the required linear equation.

5 0

2 years ago

Both and tell why pls……..

RoseWind [281]

Answer:

4) A

5) E

Step-by-step explanation:

$\frac{x}{y}=\frac{1}{10} * \frac{z}{y}$

$\frac{x}{y} =\frac{1z}{10y}$

Cross multiply the equation and you get:

$10xy=zy$

Since $\frac{a}{b}=\frac{c}{d}$ is the same thing as $ad=bc$ , you can change the equation into $\frac{x}{z} =\frac{y}{10y}$

Cancel out the y on the top and bottom and you get 1/10

$\frac{2}{3} *\frac{x}{2} =5$ , simplify and you get $\frac{x}{3} =5$ so x=15

$\frac{1}{5} * 3(x)$ is equal to $\frac{1}{5} *3(15)$ after you plug in x, and that is equal to 9

7 0

3 years ago

Write an algebraic expression that models the situation

ladessa [460]

Answer:

Step-by-step explanation:

just 19

5 0

4 years ago

Two fair number cubes are rolled. State whether the events are mutually exclusive. Explain your reasoning.

liubo4ka [24]

The answer is B because if you think about it for example if the number is 4 and 4 it would give you 8 but that’s even and if you take 3 and 3 will give you 6 also another even so if you have the same two number you can always divide it by two
Hope this helps

7 0

3 years ago

Consider the hypothetical study described below. Based solely on the information given, do you have reason to question the resu

elena-14-01-66 [18.8K]

Answer:

(B) Yes, there is reason. The TV audience might not be representative of the population.

(E) Yes, there is reason. Call-in polls tend to be biased.

Step-by-step explanation:

According to the information given we might consider two answers.

The first answer is:

<em>(B) Yes, there is reason. The TV audience might not be representative of the population.</em>

Let's remember that for a sample to be representative of a population must be random and every person must have the same probability of being selected. Here, the question is targeted only to the TV show's audience, so the results can only be interpreted for this segment of the population.

<em>(E) Yes, there is reason. Call-in polls tend to be biased.</em>

The risk is that the people who call might be influenced by the show itself and would not give an unbiased answer. This creates a bias on the sample. Besides, as stated before, not all the elements of the population can be part of the sample.

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4 years ago