Does anyone know the answer for both of these

with the major options package and destination charge, a sports car costs $24,416. the base price of the car was ten times the p

victus00 [196]

<span />x=base price
x/10=major options package
x/50=destination charge

x+x/10+x/50=24,416

x=21,800

3 0

3 years ago

You want to get from a point A on the straight shore of the beach to a buoy which is 54 meters out in the water from a point B o

anyanavicka [17]

Answer:

$x =\dfrac{45 \sqrt{6}}{ 2}$

Step-by-step explanation:

From the given information:

The diagrammatic interpretation of what the question is all about can be seen in the diagram attached below.

Now, let V(x) be the time needed for the runner to reach the buoy;

∴ We can say that,

$\mathtt{V(x) = \dfrac{70-x}{7}+\dfrac{\sqrt{54^2+x^2}}{5}}$

In order to estimate the point along the shore, x meters from B, the runner should stop running and start swimming if he want to reach the buoy in the least time possible, then we need to differentiate the function of V(x) and relate it to zero.

i.e

The differential of V(x) = V'(x) =0

= $\dfrac{d}{dx}\begin {bmatrix} \dfrac{70-x}{7} + \dfrac{\sqrt{54^2+x^2}}{5} \end {bmatrix}= 0$

$-\dfrac{1}{7}+ \dfrac{1}{5}\times \dfrac{x}{\sqrt{54^2+x^2}}=0$

$\dfrac{1}{5}\times \dfrac{x}{\sqrt{54^2+x^2}}= \dfrac{1}{7}$

$\dfrac{5x}{\sqrt{54^2+x^2}}= \dfrac{1}{7}$

$\dfrac{x}{\sqrt{54^2+x^2}}= \dfrac{1}{\dfrac{7}{5}}$

$\dfrac{x}{\sqrt{54^2+x^2}}= \dfrac{5}{7}$

squaring both sides; we get

$\dfrac{x^2}{54^2+x^2}= \dfrac{5^2}{7^2}$

$\dfrac{x^2}{54^2+x^2}= \dfrac{25}{49}$

By cross multiplying; we get

$49x^2 = 25(54^2+x^2)$

$49x^2 = 25 \times 54^2+ 25x^2$

$49x^2-25x^2 = 25 \times 54^2$

$24x^2 = 25 \times 54^2$

$x^2 = \dfrac{25 \times 54^2}{24}$

$x =\sqrt{ \dfrac{25 \times 54^2}{24}}$

$x =\dfrac{5 \times 54}{\sqrt{24}}$

$x =\dfrac{270}{\sqrt{4 \times 6}}$

$x =\dfrac{45 \times 6}{ 2 \sqrt{ 6}}$

$x =\dfrac{45 \sqrt{6}}{ 2}$

8 0

3 years ago

Factorise- 6y-15y^2<br> HELP

Citrus2011 [14]

We will take the common terms in the expressions-

Here in the expression, 3y is a common term.
So,

$6y - 15y^{2}$

$3y(2 - 5y)$

So, the answer is $3y(2 -5y)$

7 0

3 years ago

Read 2 more answers

Which of the following is an irrational number?

Serhud [2]

A. 1.9 is an irrational number

6 0

3 years ago

The graph of the function f(x) = –(x + 6)(x + 2) is shown below.Which statement about the function is true?

LekaFEV [45]

Answer:

The first statement is true.

Step-by-step explanation:

The function is f(x) = - (x + 6)(x + 2)

⇒ f(x) = - x² - 8x - 12

Now, condition for a function f(x) to be increasing at x = a is f'(a) > 0.

Now, f(x) = - x² - 8x - 12

⇒ f'(x) = -2x - 8 {Differentiating with respect to x}

Now, f'(a) = -2a - 8 {Here a can be any real value}

And, the condition for increasing function at x = a is

- 2a - 8 > 0

⇒ - 2a > 8

⇒ a < - 4

Therefore, the first statement is true i.e. the function is increasing for all real values of x where x < – 4. (Answer)

4 0

2 years ago