Brian ate 1/5 of a pie. Then Colin ate 1/5 of the pie, and David ate 1/5 of the pie. How much of the pie was left?

Write an equation for a parabola in which the set of all points in the plane are equidistant from the focus and line. F(–2, 0);

UNO [17]

The line is called the directrix. Here we have a vertical directrix, so a parabola sideways from usual.

Geometry is best done with squared distances. The squared distance from an arbitrary point (x,y) to the vertical line x=2 is $(x-2)^2.$

We equate that to the squared distance of (x,y) to the focus (-2,0):

$(x-2)^2 = (x - -2)^2 + (y - 0)^2$

$x^2 -4x + 4=x^2 +4x +4 + y^2$

$-8x = y^2$

We could call that done. A more standard form might be

$x =- \dfrac 1 8 \ y^2$

8 0

2 years ago

A student earned grades of 84, 78, 84, and 72 out of 100 on her four regular tests. She scored 78% on the final exam and 86% on

adelina 88 [10]

If the student received marks of 84, 78, 84, and 72 on her four normal tests, her weighted mean grade is 81.2 percent.

The mean is described as a single number that indicates either the closed value for each item in the collection of data or the mean value for the whole set of data.

On her four regular tests, a student had grades of 84, 78, 84, and 72 out of 100. She received 86 percent on her class projects and 78 percent on the final test.

You may compute the weighted mean as follows:

$\rm W_m= 0.4 \times ( \frac{84+78+84+72}{4} )+0.3 \times 78 +0.1 \times 86 + 0.2 \times 87 \\\\ W_m= 81.2 \%$

Hence, if the student had marks of 84, 78, 84, and 72 on her four normal tests, her weighted mean grade would be 81.2 percent.

To learn more about the mean refer;

brainly.com/question/22871228

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5 0

1 year ago

Which of the following is a solution to the inequality below?

BaLLatris [955]

I did the math but I got -4 so maybe -14

6 0

2 years ago

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The sampling examples below use either the stratified or the cluster method of sampling. Select the examples that use the strati

Marysya12 [62]

A landlord wants to know the average income of his tenants. He selects three of his eight apartment complexes and collects income information from several randomly chosen tenants within the selected complexes.

A health agency needs to assess the performance of hospitals in a region but does not have the resources to evaluate each hospital. To reduce costs, the agency selects 5 of the 23 hospitals in the region and samples data related to performance from randomly chosen days and times.

Answer: Options D and E.

Explanation:

Cluster sampling is a sampling plan used when mutually homogeneous yet internally heterogeneous groupings are evident in a statistical population. It is often used in marketing research. In this sampling plan, the total population is divided into these groups and a simple random sample of the groups is selected.

Stratified sampling is a probability sampling technique wherein the researcher divides the entire population into different subgroups or strata, then selects the final subjects proportionally from the different strata.

8 0

2 years ago

Hello how are you today. Question 2(×+-5)+×=×+(-6)

andre [41]

Answer:

x = 2

General Formulas and Concepts:

Pre-Algebra

Order of Operations: BPEMDAS

Brackets
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

Left to Right

Distributive Property

Equality Properties

Multiplication Property of Equality
Division Property of Equality
Addition Property of Equality
Subtraction Property of Equality

Algebra I

Terms/Coefficients

Step-by-step explanation:

Step 1: Define

Identify

2(x + -5) + x = x + (-6)

Step 2: Solve for x

[Distributive Property] Distribute 2: 2x - 10 + x = x - 6
[Addition] Combine like terms (x): 3x - 10 = x - 6
[Subtraction Property of Equality] Subtract x on both sides: 2x - 10 = -6
[Addition Property of Equality] Add 10 on both sides: 2x = 4
[Division Property of Equality] Divide 2 on both sides: x = 2

6 0

2 years ago

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