Which is the answer to this?

What is 4.5x + 2.5(x - 4)

marysya [2.9K]

Answer:

7x-10

Step-by-step explanation:

4 0

4 years ago

My son hasn't knows how to do that can somebody help him please .

kobusy [5.1K]

A ratio compares two quantities.

How may days are in May? <span>31
How many days in a year? </span>365

Now, we are being asked to compare may to a year.

Answer: 31 to 365

Now, the other is easy also.

A triangle has 3 sides, and a square has 4.

Answer: 3 to 4

Find equal ratio's

8/12 = 2/3 = 4/6 = 16/24

20/25 = 4/5 = 40/50 = 80/100

Done! Enjoy! :) I hope I helped your son. Take care.

3 0

3 years ago

Does anyone wanna be friends lol?

USPshnik [31]

Answer:

hahaha me

Step-by-step explanation:

...actually how old are you though lol

7 0

3 years ago

Read 2 more answers

Five times the sum of a number and 27 is greater than or equal to six times the sum of that number and 26. What is the

natka813 [3]

Answer:

-22.2

Step-by-step explanation:

Then, because the problem states "is at least" we know this is an inequality problem and specifically the inequality operator is:

≥

Now, we can write and solve the inequality as:

5(x+26)≥19(5x(5×26)≥195x+130≥195x+130−130≥19−1305x+0≥−1115x≥-1115x5≥−11155x5≥−22.2x≥−22.2

The number is at least

−22.2 or the number is greater than or equal to −22.2

8 0

3 years ago

Use the method of Lagrange multipliers to find the dimensions of the rectangle of greatest area that can be inscribed in the ell

Tanzania [10]

Answer:

Length (parallel to the x-axis): $2 \sqrt{2}$ ;

Height (parallel to the y-axis): $4\sqrt{2}$ .

Step-by-step explanation:

Let the top-right vertice of this rectangle $(x,y)$ . $x, y >0$ . The opposite vertice will be at $(-x, -y)$ . The length the rectangle will be $2x$ while its height will be $2y$ .

Function that needs to be maximized: $f(x, y) = (2x)(2y) = 4xy$ .

The rectangle is inscribed in the ellipse. As a result, all its vertices shall be on the ellipse. In other words, they should satisfy the equation for the ellipse. Hence that equation will be the equation for the constraint on x and y.

For Lagrange's Multipliers to work, the constraint shall be in the form: $g(x, y) =k$ . In this case

$\displaystyle g(x, y) = \frac{x^{2}}{4} + \frac{y^{2}}{16}$ .

Start by finding the first derivatives of $f(x, y)$ and $g(x, y)$ with respect to x and y, respectively:

$f_x = y$ ,
$f_y = x$ .

$\displaystyle g_x = \frac{x}{2}$ ,
$\displaystyle g_y = \frac{y}{8}$ .

This method asks for a non-zero constant, $\lambda$ , to satisfy the equations:

$f_x = \lambda g_x$ , and

$f_y = \lambda g_y$ .

(Note that this method still applies even if there are more than two variables.)

That's two equations for three variables. Don't panic. The constraint itself acts as the third equation of this system:

$g(x, y) = k$ .

$\displaystyle \left\{ \begin{aligned} &y = \frac{\lambda x}{2} && (a)\\ &x = \frac{\lambda y}{8} && (b)\\ & \frac{x^{2}}{4} + \frac{y^{2}}{16} = 1 && (c)\end{aligned}\right.$ .

Replace the $y$ in equation $(b)$ with the right-hand side of equation $(b)$ .

$\displaystyle x = \lambda \frac{\lambda \cdot \dfrac{x}{2}}{8} = \frac{\lambda^{2} x}{16}$ .

Before dividing both sides by $x$ , make sure whether $x = 0$ .

If $x = 0$ , the area of the rectangle will equal to zero. That's likely not a solution.

If $x \neq 0$ , divide both sides by $x$ , $\lambda = \pm 4$ . Hence by equation $(b)$ , $y = 2x$ . Replace the $y$ in equation $(c)$ with this expression to obtain (given that $x, y >0$ ) $x = \sqrt{2}$ . Hence $y = 2x = 2\sqrt{2}$ . The length of the rectangle will be $2x = 2\sqrt{2}$ while the height will be $2y = 4\sqrt{2}$ . If there's more than one possible solutions, evaluate the function that needs to be maximized at each point. Choose the point that gives the maximum value.

7 0

3 years ago