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2 years ago

HELP ASAP

Mathematics

2 answers:

evablogger [386]2 years ago

7 0

2,072 millimeters
207.2 centimeters

umka21 [38]2 years ago

4 0

Answer:

49 mm

Step-by-step explanation:

A scale factor is the number you multiply a side length by to find the image. This means we multiply MN, which is 28 mm, by the scale factor, 7/4:

28(7/4) = 196/4 = 49

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bekas [8.4K]

the height decreases

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2 years ago

Identify the vertex for the graph of y = −3x^2 + 6x − 4

algol [13]

Answer:

the vertex is (1,-1)

Step-by-step explanation:

y = −3x^2 + 6x − 4

the vertex is at

h= -b/2a where ax^2 +bx+c

h= -6/2(-3)

h= -6/-6

h=1

substitute this in to find the y value

y = -3(1)^2 +6(1)-4

y = -3+6-4

y = -1

the vertex is (1,-1)

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2 years ago

What is the perimeter of the triangle expressed as a polynomial?

ratelena [41]

Add the polynomials together:
(5x-2)+(2x-3)+(4x+3)
Combine like terms:
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8 0

2 years ago

The diagram shows a sketch of John's yard. He wants to plant grass, so he must calculate the area of the yard. The distance from

Arturiano [62]

The area of the yard is 50,600 square feet.

Option: C.

<u>Step-by-step explanation:</u>

The given information forms a trapezoid.

The AB is the upper base (a) and its length is 200 feet.

The CD is the lower base (b) and its length is 260 feet.

A straight line distance from AB and CD is the height (h) and its measures as 220 feet.

The area of trapezoid A= $\frac{a+b}{2} (h)$ .

A= $\frac{200+260}{2} (220)$ .

= $\frac{460}{2}(220)$ .

=230(220).

=50600 $ft^2.$

Thus the area of John's yard is 50,600 square feet.

3 0

3 years ago

Arm Span(x) Height(y)

natita [175]

Answer:

Here's what I get.

Step-by-step explanation:

1. Representation of data

I used Excel to create a scatterplot of the data, draw the line of best fit, and print the regression equation.

2. Line of best fit

(a) Variables

I chose arm span as the dependent variable (y-axis) and height as the independent variable (x-axis).

It seems to me that arm span depends on your height rather than the other way around.

(b) Regression equation

The calculation is easy but tedious, so I asked Excel to do it.

For the equation y = ax + b, the formulas are

$a = \dfrac{\sum y \sum x^{2} - \sum x \sumxy}{n\sum x^{2}- \left (\sum x\right )^{2}}\\\\b = \dfrac{n\sumx y - \sum x \sumxy}{n\sum x^{2}- \left (\sum x\right )^{2}}$

This gave the regression equation:

y = 1.0595x - 4.1524

(c) Interpretation

The line shows how arm span depends on height.

The slope of the line says that arm span increases about 6 % faster than height.

The y-intercept is -4. If your height is zero, your arm length is -4 in (both are impossible).

(d) Residuals

$\begin{array}{cccr}&\textbf{Arm Span} & \textbf{Arm Span}&\\\textbf{Height/in} &\textbf{Actual} & \textbf{Predicted}&\textbf{Residual}\\25 & 19 & 22.3 & -3.3\\40 & 41 & 38.2 & 2.8\\55 & 51 & 54.1 & -3.1\\65 & 67 & 62.6 & 4.4\\ \end{array}$

The residuals appear to be evenly distributed above and below the predicted values.

A graph of all the residuals confirms this observation.

The equation usually predicts arm span to within 4 in.

(e) Predictions

(i) Height of person with 66 in arm span

$\begin{array}{rcl}y& = & 1.0595x - 4.1524\\66 & = & 1.0595x - 4.1524\\70.1524 & = & 1.0595x\\x & = & \dfrac{70.1524}{1.0595}\\\\& = & \textbf{66 in}\\\end{array}\\\text{A person with an arm span of 66 in should have a height of about $\large \boxed{\textbf{66 in}}$}$

(ii) Arm span of 74 in tall person

$\begin{array}{rcl}y& = & 1.0595x - 4.1524\\& = & 1.0595\times74 - 4.1524\\& = & 78.4030 - 4.1524\\& = & \textbf{74 in}\\\end{array}\\\text{ A person who is 74 in tall should have an arm span of $\large \boxed{\textbf{74 in}}$}$

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2 years ago