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3 years ago

The price of a notebook was

Mathematics

1 answer:

aleksandr82 [10.1K]3 years ago

8 0

(3.90 - 3.40) / (3.90) = 0.50 / 3.90 = 0.128 x 100 = 12.8%

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Which of the following relations are functions?

Alisiya [41]

{(c,e),(c,d),(c,b)} is NOT a function since the input c has multiple outputs (e,d,b). So choice B is out

{(b,b),(c,d),(d,c),(c,a)} is NOT a function either. The input 'c' corresponds to the output 'd' and 'a' at the same time. So choice C is out too

Choices A and D are the answer. They are functions since any given input corresponds to exactly one output.

7 0

2 years ago

Read 2 more answers

7x-2y=-5which ordered pair is a solution of the equation

sashaice [31]

Answer:

What ordered pair my closest answer is y = 5/2+7x/2

Step-by-step explanation:

Subtract 7x from both sides of the equation.

3 0

2 years ago

The number of salmon swimming upstream to spawn is approximated by the following function:

umka2103 [35]

Answer:

The water temperature that produces the maximum number of salmon swimming upstream is approximately 12.305 degrees Celsius.

Step-by-step explanation:

Let $S(x) = -x^{3}+2\cdot x^{2}+405\cdot x +4965$ , for $6 \leq x \leq 20$ . $x$ represents the temperature of the water, measured in degrees Celsius, and $S$ is the number of salmon swimming upstream to spawn, dimensionless.

We compute the first and second derivatives of the function:

$S'(x) = -3\cdot x^{2}+4\cdot x +405$ (Eq. 1)

$S''(x) = -6\cdot x +4$ (Eq. 2)

Then we equalize (Eq. 1) to zero and solve for $x$ :

$-3\cdot x^{2}+4\cdot x +405 = 0$

And all roots are found by Quadratic Formula:

$x_{1} \approx 12.305\,^{\circ}C$ , $x_{2}\approx -10.971\,^{\circ}C$

Only the first root is inside the given interval of the function. Hence, the correct answer is:

$x \approx 12.305\,^{\circ}C$

Now we evaluate the second derivative at given result. That is:

$S''(12.305) = -6\cdot (12.305)+4$

$S''(12.305) = -69.83$

According to the Second Derivative Test, a negative value means that critical value leads to a maximum. In consequence, the water temperature that produces the maximum number of salmon swimming upstream is approximately 12.305 degrees Celsius.

5 0

3 years ago

Enter the coordinates of the point on the unit circle at the given angle. 135° (-VII, VI Enter

vekshin1

Related angle is 45 degrees, set up a triangle and use exact trig values to solve for x and y, then rationalise the denominators

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3 years ago

Which one of the following statements about the Fed is

ivann1987 [24]

A because the feed sets discounts rate and primes

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2 years ago