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3 years ago

Two less than the product of a number and -5 is-42

Mathematics

1 answer:

HACTEHA [7]3 years ago

6 0

The answer is 8

Explanation-
-5x = -40
x = 8

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A class tracked the number of hours each student plays video games in a week. Answer the questions below.

dsp73

The answer to this question is B

4 0

4 years ago

A lighthouse is located on a small island 2 km away from the nearest point P on a straight shoreline and its light makes four re

ddd [48]

Answer:

62.8 km per min

Step-by-step explanation:

Let the diagram of this situation is shown below,

In which $\theta$ is the angle made by light to the straight line joining the lighthouse and P,

∵ Light makes 4 revolutions per minute.

Also, 1 revolution = $2\pi$ radians

So, the change in angle with respect to t ( time ),

$\frac{d\theta}{dt}=8\pi\text{ radians per min}$

Let x be the distance of beam from P,

$\implies \tan \theta = \frac{x}{2}$

Differentiating with respect to x,

$\sec^2 \theta \frac{d\theta}{dt}=\frac{1}{2}\frac{dx}{dt}$

$(1+\tan^2 \theta) (8\pi) = \frac{1}{2}\frac{dx}{dt}$

$(1+\frac{x^2}{2^2})(8\pi) = \frac{1}{2}\frac{dx}{dt}$

If x = 1 km,

$(1+\frac{1}{4})8\pi =\frac{1}{2}\frac{dx}{dt}$

$\frac{5}{4}8\pi = \frac{1}{2}\frac{dx}{dt}$

$\implies \frac{dx}{dt}=\frac{80\pi}{4}= 20\pi\approx 62.8\text{ km per min}$

Hence, the beam of light moving along the shoreline with the speed of 62.8 km per min

7 0

4 years ago

Simplify using the order of operations.<br> 9−4 ·5+6

Aleksandr-060686 [28]

we know that the multiplication comes first in the family then we start from left to right

4 x 5= 20

9-20 = -11

-11 + 6 = -5

there you go!

3 0

3 years ago

Read 2 more answers

Two square rooms have a total floor area of 89m2. One room is 3m longer each way than the other. Find the dimensions of the two

Rudiy27

Answer:

Step-by-step explanation:

Let the smaller room have an area of x^2

Let the larger room have an area of (x + 3)^2

(x+3) ^2 + x^2 = 89 Be careful not to make it 89^2.

x^2 + 6x + 9 + x^2 = 89 Expand the binomial squared

2x^2 + 6x + 9 - 89 = 0 Subtract 89 from both sides

2x^2 + 6x + 9 - 89 = 0 Combine

2x^2 + 6x - 90=0 Divide by 2

x^2 + 3x - 45 = 0 This factors.

(x + 9)(x- 5) = 0

X + 9 gives nothing useful

x - 5 = 0

x = 5

x + 3 = 5+3 = 8

So the answer is A

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3 years ago

HELP HELP HELP HELP <br><br> What is the equation of the trend line in the scatter plot ?

NISA [10]

Where is the link to your question? I can't answer thing without a link my guy- :/

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3 years ago