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3 years ago

Surface area in terms of pi?

Mathematics

1 answer:

Lunna [17]3 years ago

5 0

$\bf \textit{volume of a sphere}\\\\ V=\cfrac{4\pi r^3}{3}~~ \begin{cases} r=radius\\ \cline{1-1} V=972\pi \end{cases}\implies 972\pi =\cfrac{4\pi r^3}{3}\implies 2916\pi =4\pi r^3 \\\\\\ \cfrac{2916}{4\pi }=r^3\implies 729=r^3\implies \sqrt[3]{729}=r\implies 9=r \\\\[-0.35em] ~\dotfill\\\\ \textit{surface area of a sphere}\\\\ SA=4\pi r^2\qquad \qquad \implies SA=4\pi (9)^2\implies \boxed{SA=324\pi }$

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The predicted calories in food items based on grams of fat are represented by the residual plot.

VashaNatasha [74]

Answer:

The correct option is;

C. The pattern is random, indicating a good fit for a linear model

Step-by-step explanation:

A graph that has the residuals (the difference between the value observed and the value expected (regression analysis) on the vertical axis and the variable that is not affected by the other variables (independent variable) on the x or horizontal axis is known as a residual plot

A linear regression model is suited in a situation where the points are dispersed randomly on both sides of the horizontal axis

Therefore, given that the first point is below the horizontal axis and the next point is above the horizontal axis, while the third and the fourth points are below the horizontal axis, the fifth, sixth, and seventh points are above the horizontal axis and the eighth point is below the horizontal axis, the points are random around the horizontal axis, indicating the suitability of a linear regression model.

3 0

3 years ago

Please I need help ASAP<br>pls explain your answer

USPshnik [31]

Answer:

47.62 cm

Step-by-step explanation:

ABCD is a rhombus. Each side measures 15 cm.

m<A = 60°.

Here are some properties of a rhombus:

Opposite angles of a rhombus are congruent.

m<C = m<A = 60°

m<ADC = m<ABC

The sum of the measures of the interior angles of a quadrilateral is 360°.

The diagonals are perpendicular bisectors of each other.

m<A + m<C + m<ADC + m<ABC = 360°

60° + 60° + 2m<ADC = 360°

2m<ADC = 240°

m<ADC = 120°

Each diagonal of a rhombus bisects a pair of congruent, opposite angles.

m<ADB + m<CDB = m<ADC

m<ADB = m<CDB

m<ADB + m<ADB = 120°

m<ADB = 60°

Triangle ABD had two angles, <A and <ADB, that measure 60°. Therefore, the third angle, <ABD also measures 60°. That makes triangle ABD an equilateral triangle.

Draw segment AT.

T is the midpoint of BD. The segment AT is the perpendicular bisector of segment BD. Triangle ATD is a 30-60-90 triangle.

Using the ratio of the lengths of the sides of a 30-60-90 triangle, we can calculate the length of AT which is the radius of circle A.

TD : AT : AD

1 : √3 : 2

AD = 15 cm

TD = AD/2

AT = √3 × TD

AT = (AD√3)/2

AT = 7.5√3 = 12.99

AQ = 12.99

perimeter = QD + PB + m(arc)PTQ + BC + CD