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3 years ago

Help with substitution! (With pictures-2 separate questions) thanks!

Mathematics

1 answer:

Art [367]3 years ago

5 0

Answer:

Explanation contains answer.

Step-by-step explanation:

Question 1:

I would perfer to solve the first equation for y because there is only one operation to perform on both sides and it is subtraction of 2x on both sides.

The other equation requires two steps to isolate y; subtracting 3x on both sides then multiplying both sides by -1.

So basically solving the first one for y because it has coefficient 1.

Question 2:

They solved the 2nd equation for y and plugged into itself instead of plugging it into 1st equation.

You might be interested in

Find the equation of a parabola with vertex at the origin and focus (0, -32).

mrs_skeptik [129]

Answer:

x^2 = -128y

Step-by-step explanation:

The general formula for this type of parabola is x^2 = 4ay where a is the y coordinate of the focus. So 4a = 4*-32 = 1-28.

So the answer is x^2 = -128y

4 0

4 years ago

Subtract (2/7 -5/21 ) from the sum of 3/4, 5/7 and 7/12

timofeeve [1]

Answer:

answer is 2

Step-by-step explanation:

4 0

3 years ago

In a video game, a bird is flung on a sling shot and follows a parabolic path. The path of the bird can be modeled by the equati

Novay_Z [31]

Answer:

The bird will take 0.88 seconds to reach a height of 40 feet in the air for the first time

Step-by-step explanation:

we have

$h=-16t^2+55t+4$

This is a vertical parabola open downward

The vertex represent a maximum

where

h is the height of the bird

t is the amount of time, in seconds, the bird had been in the air

For h=40 ft

substitute in the quadratic equation

$40=-16t^2+55t+4$

$-16t^2+55t+4-40=0$

$-16t^2+55t-36=0$

The formula to solve a quadratic equation of the form

$ax^{2} +bx+c=0$

is equal to

$x=\frac{-b\pm\sqrt{b^{2}-4ac}} {2a}$

in this problem we have

$-16t^2+55t-36=0$

$a=-16\\b=55\\c=-36$

substitute in the formula

$x=\frac{-55\pm\sqrt{55^{2}-4(-16)(-36)}} {2(-16)}$

$x=\frac{-55\pm\sqrt{721}} {-32}$

$x=\frac{-55+\sqrt{721}} {-32}=0.88\ sec$

$x=\frac{-55-\sqrt{721}} {-32}=2.56\ sec$

therefore

The bird will take 0.88 seconds to reach a height of 40 feet in the air for the first time

3 0

3 years ago

When is it better to use a table When is it better to use a scatter plot

34kurt

Management information system requires tables, Tables are used only if a person is trying to analyse data and understand its business by summarizing.It is the 1st step of data analysis collecting data. Scatter plot is used when there is a question of association of two or three variable.

Step-by-step explanation:

Table is the matrix to stack up the data in there respective columns.
It is the most important setup to analysis.
It's better used collecting data for any projects or business.
Tables are even used for Bio statistics and Analytics.
Databases uses tables for one query table to another query table.
Scatter plot is dotted plot which analyse two variables.
Example if a project is eating chocolates in gram in x axis.
Gaining weight in y axis two variables are used to predict and outcome.
If a person eats this amount of chocolate it will gain this wait.
Association rules, contingency statistics and rest.

6 0

4 years ago

Let event Aequalssubject is telling the truth and event Bequalspolygraph test indicates that the subject is lying. Use your own

pochemuha

Answer:

C is the right answer

Step-by-step explanation:

In this case we have the events

A: The subject is telling the truth.

B: The the polygraph indicates that the subject is lying

Recall that P(B|A) is defined as the probability that the event B occurs given that the event has already occurred, and is equals to P(B∩A)/P(A).

So, with the events we have defined, P(B|A) indicates the probability that the polygraph indicates lying given that the subject is actually telling the truth.

The most suitable answer is thus, C

3 0

3 years ago