All categories

3 years ago

I'm not quite understanding how to solve these word problems

Mathematics

1 answer:

scoundrel [369]3 years ago

6 0

I'll help you on the first one.
Anya test scores are 78 and 91.
She has one more test and want to average between an 80-89 inclusive.
Lets set up a inequality and call the remaining test x.
80<=(78+91+x)/3<=89
Multiply everything by 3
240<=169+x<=267
Subtract 169 from everything
71<=x<=98
In interval notation that would be [71,98]
In set notation that would be{x|71<=x<=98}
For the graph, I don't really understand. I think you just graph 71<=x<=98.

You might be interested in

Write the prime factorization of 675 using exponent

matrenka [14]

675 : 5 = 135

135 : 5 = 27

27 : 3 = 9

9 : 3 = 3

3 : 3 = 1

675 = 5 · 5 · 3 · 3 · 3 = 5² · 3³

4 0

3 years ago

Convert the following degree measure to radian measure. 90 degrees

Ray Of Light [21]

90 degrees converted to radians is pi/2 or π/2 radians.

4 0

4 years ago

PLEASE HELP EASY WORK GIVING BRAINLIEST REPORTING FALSE ANSWERS

LuckyWell [14K]

It is 70 because common sense people

7 0

3 years ago

Show tan(???? − ????) = tan(????)−tan(????) / 1+tan(????) tan(????)<br> .

anyanavicka [17]

Answer:

See the proof below

Step-by-step explanation:

For this case we need to proof the following identity:

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

We need to begin with the definition of tangent:

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

So we can replace into our formula and we got:

$tan(x-y) = \frac{sin(x-y)}{cos(x-y)}$ (1)

We have the following identities useful for this case:

$sin(a-b) = sin(a) cos(b) - sin(b) cos(a)$

$cos(a-b) = cos(a) cos(b) + sin (a) sin(b)$

If we apply the identities into our equation (1) we got:

$tan(x-y) = \frac{sin(x) cos(y) - sin(y) cos(x)}{sin(x) sin(y) + cos(x) cos(y)}$ (2)

Now we can divide the numerator and denominato from expression (2) by $\frac{1}{cos(x) cos(y)}$ and we got this:

$tan(x-y) = \frac{\frac{sin(x) cos(y)}{cos(x) cos(y)} - \frac{sin(y) cos(x)}{cos(x) cos(y)}}{\frac{sin(x) sin(y)}{cos(x) cos(y)} +\frac{cos(x) cos(y)}{cos(x) cos(y)}}$

And simplifying we got:

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

And this identity is satisfied for all:

$(x-y) \neq \frac{\pi}{2} +n\pi$

8 0

3 years ago

A document is awarded to a person for completing a course of a study that does not lead to a degree is called a ____.

tatiyna

I got you. The answer would be A (Certificate)

8 0

3 years ago