How do you find perimeter of a rectangle?

A restaurant bill is $84.96. Estimate a 20% tip. Estimate a 15% tip.

Lisa [10]

If you have to estimate I will put $85 and then to find 20 % you just have to kniw that 10% is equal to 8.5 you just move a decimal then you just add 8.5 plus 8.5 = 17 so 20% of 85 is equal to $17 and to find 15% you already know how much is 10%=8.5 so you just need to find 5% that is equal to 4.25 and then you just add 4.25 to 8.5 and that's equal to 12.75

20%= 17
15%=12.5

4 0

3 years ago

Read 2 more answers

Given m∥n, find the value of x and y.

Korolek [52]

Answer:

x = 15

y = 63

Step-by-step explanation:

9x - 7 + 4x - 8 = 180

13x = 195

x = 15

9x - 7 = 2y + 2

126 = 2y

y = 63

8 0

2 years ago

Application of the least squares method results in values of the y-intercept and the slope that minimizes the sum of the squared

alisha [4.7K]

Answer:

The least squares method results in values of the y-intercept and the slope, that minimizes the sum of the squared deviations between the observed (actual) value and the fitted value.

Step-by-step explanation:

The method of least squares works under these assumptions

The best fit for a data collection is a function (sometimes called curve).
This function, is such that allows the minimal sum of difference between each observation and the expected value.
The expected values are calculated using the fitting function.
The difference between the observation, and the expecte value is know as least square error.

7 0

3 years ago

Write an equation in slope-intercept form of the line that passes through (-1, 4) and (0, 2).

arsen [322]

Answer:

$y=-2x+2$

Step-by-step explanation:

Hi there!

Slope-intercept form: $y=mx+b$ where m is the slope and b is the y-intercept (the value of y when the line crosses the y-axis)

<u>1) Determine the slope</u>

$m=\frac{y_2-y_1}{x_2-x_1}$ where the two given points are $(x_1,y_1)$ and $(x_2,y_2)$

Plug in the given points (-1, 4) and (0, 2)

$=\frac{2-4}{0-(-1)}\\=\frac{-2}{0+1}\\=\frac{-2}{1}\\= -2$

Therefore, the slope of the line is -2. Plug this into $y=mx+b$ :

$y=-2x+b$

<u>2) Determine the y-intercept</u>

$y=-2x+b$

Recall that the y-intercept is the value of y when the line crosses the y-axis, meaning that the y-intercept occurs when x is equal to 0.

One of the given points is (0,2). Notice how y=2 when x=0. Therefore, the y-intercept of the line is 2.

Plug this back into the equation:

$y=-2x+2$

I hope this helps!

6 0

3 years ago

Sketch the domain D bounded by y = x^2, y = (1/2)x^2, and y=6x. Use a change of variables with the map x = uv, y = u^2 (for u ?

cluponka [151]

Under the given transformation, the Jacobian and its determinant are

$\begin{cases}x=uv\\y=u^2\end{cases}\implies J=\begin{bmatrix}v&u\\2u&0\end{bmatrix}\implies|\det J|=2u^2$

so that

$\displaystyle\iint_D\frac{\mathrm dx\,\mathrm dy}y=\iint_{D'}\frac{2u^2}{u^2}\,\mathrm du\,\mathrm dv=2\iint_{D'}\mathrm du\,\mathrm dv$

where $D'$ is the region $D$ transformed into the $u$ - $v$ plane. The remaining integral is the twice the area of $D'$ .

Now, the integral over $D$ is

$\displaystyle\iint_D\frac{\mathrm dx\,\mathrm dy}y=\left\{\int_0^6\int_{x^2/2}^{x^2}+\int_6^{12}\int_{x^2/2}^{6x}\right\}\frac{\mathrm dx\,\mathrm dy}y$

but through the given transformation, the boundary of $D'$ is the set of equations,

$\begin{array}{l}y=x^2\implies u^2=u^2v^2\implies v^2=1\implies v=\pm1\\y=\frac{x^2}2\implies u^2=\frac{u^2v^2}2\implies v^2=2\implies v=\pm\sqrt2\\y=6x\implies u^2=6uv\implies u=6v\end{array}$

We require that $u>0$ , and the last equation tells us that we would also need $v>0$ . This means $1\le v\le\sqrt2$ and $0$ , so that the integral over $D'$ is

$\displaystyle2\iint_{D'}\mathrm du\,\mathrm dv=2\int_1^{\sqrt2}\int_0^{6v}\mathrm du\,\mathrm dv=\boxed6$

4 0

3 years ago