Ask question

Ask question

All categories

3 years ago

11

Daniel had a social studies quiz he answered 87 out of 100 exercises correctly write a decimal to show the part of the quiz that

Daniel answered correctly

1 answer:

ss7ja [257]3 years ago

6 0

Answer:

the answer is 0.87 good luck

You might be interested in

Suppose cos(x)= -1/3, where π/2 ≤ x ≤ π. What is the value of tan(2x). EDGE

AVprozaik [17]

Answer:

D

Step-by-step explanation:

We are given that:

$\displaystyle \cos x = -\frac{1}{3}\text{ where } \pi /2 \leq x \leq \pi$

And we want to find the value of tan(2<em>x</em>).

Note that since <em>x</em> is between π/2 and π, it is in QII.

In QII, cosine and tangent are negative and only sine is positive.

We can rewrite our expression as:

$\displaystyle \tan(2x)=\frac{\sin(2x)}{\cos(2x)}$

Using double angle identities:

$\displaystyle \tan(2x)=\frac{2\sin x\cos x}{\cos^2 x-\sin^2 x}$

Since cosine relates the ratio of the adjacent side to the hypotenuse and we are given that cos(<em>x</em>) = -1/3, this means that our adjacent side is one and our hypotenuse is three (we can ignore the negative). Using this information, find the opposite side:

$\displaystyle o=\sqrt{3^2-1^2}=\sqrt{8}=2\sqrt{2}$

So, our adjacent side is 1, our opposite side is 2√2, and our hypotenuse is 3.

From the above information, substitute in appropriate values. And since <em>x</em> is in QII, cosine and tangent will be negative while sine will be positive. Hence:

<h2> $\displaystyle \tan(2x)=\frac{2(2\sqrt{2}/3)(-1/3)}{(-1/3)^2-(2\sqrt{2}/3)^2}$ </h2>

Simplify:

$\displaystyle \tan(2x)=\frac{-4\sqrt{2}/9}{(1/9)-(8/9)}$

Evaluate:

$\displaystyle \tan(2x)=\frac{-4\sqrt{2}/9}{-7/9} = \frac{4\sqrt{2}}{7}$

The final answer is positive, so we can eliminate A and B.

We can simplify D to:

$\displaystyle \frac{2\sqrt{8}}{7}=\frac{2(2\sqrt{2}}{7}=\frac{4\sqrt{2}}{7}$

So, our answer is D.

7 0

3 years ago

Write the least common multiple of 120 and 80

Olin [163]

The least common multiple would be 240.
120(2)=240 AND
80(3)=240

6 0

3 years ago

Please I need the answer PLEASEEEEEEEEEEEEEEEEEE!

Ilya [14]

Answer: The first one

Step-by-step explanation:

3 0

3 years ago

A second game uses spinner B. A player must spin a Wto win. Explain how to find the experimental probability of spinning a W.

Volgvan

Answer:

sorry foe being late

Step-by-step explanation:

8 0

3 years ago

A line passes through the points (–5, 2) and (10, –1). Which is the equation of the line?

beks73 [17]

Slope = (2 + 1) / (-5 - 10) = -3/15 = - 1/5

Equation

y - 2 = -1/5 (x + 5)

y - 2 = -1/5 x - 1

y = -1/5 x + 1

Answer

y = -1/5 x + 1

6 0

3 years ago

Read 2 more answers