What is the answer to 7(5-8x)

Jina used a tots of 2 1/6 gallons of gas while driving her car. Each hour she was driving, she used 7/8 gallons of gas. What was

marysya [2.9K]

2 1/6 ÷ 7/8= 2 10/21 h
hope this helps!

8 0

2 years ago

Considering only the values of β for which sinβtanβsecβcotβ is defined, which of the following expressions is equivalent to sinβ

-Dominant- [34]

Answer:

$\tan(\beta)$

Step-by-step explanation:

For many of these identities, it is helpful to convert everything to sine and cosine, see what cancels, and then work to build out to something. If you have options that you're building toward, aim toward one of them.

${\tan(\theta)}={\dfrac{\sin(\theta)}{\cos(\theta)}$ and ${\sec(\theta)}={\dfrac{1}{\cos(\theta)}$

Recall the following reciprocal identity:

$\cot(\theta)=\dfrac{1}{\tan(\theta)}=\dfrac{1}{ \left ( \dfrac{\sin(\theta)}{\cos(\theta)} \right )} =\dfrac{\cos(\theta)}{\sin(\theta)}$

So, the original expression can be written in terms of only sines and cosines:

$\sin(\beta)\tan(\beta)\sec(\beta)\cot(\beta)$

$\sin(\beta) * \dfrac{\sin(\beta) }{\cos(\beta) } * \dfrac{1 }{\cos(\beta) } * \dfrac{\cos(\beta) } {\sin(\beta) }$

$\sin(\beta) * \dfrac{\sin(\beta) \!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!{---}}{\cos(\beta) \!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!{---}} * \dfrac{1 }{\cos(\beta) } * \dfrac{\cos(\beta) \!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!{---}} {\sin(\beta) \!\!\!\!\!\!\!\!\!\!\!\!\!\!\!\!{---}}$

$\sin(\beta) *\dfrac{1 }{\cos(\beta) }$

$\dfrac{\sin(\beta)}{\cos(\beta) }$

Working toward one of the answers provided, this is the tangent function.

The one caveat is that the original expression also was undefined for values of beta that caused the sine function to be zero, whereas this simplified function is only undefined for values of beta where the cosine is equal to zero. However, the questions states that we are only considering values for which the original expression is defined, so, excluding those values of beta, the original expression is equivalent to $\tan(\beta)$ .

8 0

1 year ago

Solve the proportion to determine the value of x. <br><br> 2x / 5 = x+3 / 3

ale4655 [162]

When you solve a proportion, your first step should be to cross-multiply.

$\frac{2x}{5}$ = $\frac{x + 3}{3}$

When you cross-multiply, you should get this equation:

(2x)(3) = (x + 3)(5)

Now, solve it using algebra.

(2x)(3) = (x + 3)(5) Multiply
6x = 5x + 15 Subtract 5x from both sides
x = 15

The value of x is 15.

4 0

3 years ago

Find the area of the regular polygon below and round your answer to the nearest tenth.

stira [4]

The 9-sided polygon will have a central angle between the vertex and the center of one side of 360°/(2*9) = 20°. Then the apothem is
a = (6 in/2)*cot(20°) ≈ 8.242432 in
The perimeter is 9*6 in = 54 in, so the area is
A = (1/2)Pa = (1/2)*(54 in)*(8.242432 in) ≈ 222.5 in²

4 0

3 years ago

If a denotes some event, what does upper a overbara denote? if p(a)equals=0.9930.993, what is the value of p(upper a overba

masya89 [10]

P(A) = 0.993 is the probability of event A
_
P(A) is the probability of not A (note that I am trying to place a bar over A. I hope you can see it, else it is because the editor did not show it as I intended)

Then, use the fact that the probability of A plus the probability not A is equal to 1:
                  _
=> P(A) + P(A) = 1
       _
=> P(A) = 1 - P(A) = 1 - 0.993 = 0.007

So, the answers are:
      _
1) P(A) = 0.07
             _
2) Yes, A is unlikely because its probability is very low.

5 0

3 years ago

What is the answer to 7(5-8x) > 147