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3 years ago

Given the system of equations, what is the solution? x + 2y = 7 x - 2y = -1

1 answer:

4 0

Add the 2 equations to eliminate the 2y. We get

2x = 6

x = 3

Plug x = 3 into the first equation:-

3 + 2y = 7
2y = 7 - 3 = 4

y = 2

Answer is x = 3 and y = 2

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The following blueprint of a kitchen has dimensions of 7 inches by 7 inches. The island has been highlighted in red 3 1/2 The is

Talja [164]

So assuming 1 3/4 feet by feet means 1 3/4 feet by 1 foot,

island actual dimentions=1 3/4 feet by 1 foot

scale=1 inch=1 feet
logically, blueprints are smaller so for every real foot, 1 inch is drawn on the scale
so change every foot to inch

so the island on the blueprint=1 3/4 inch by 1 inch

6 0

3 years ago

Given a joint PDF, f subscript X Y end subscript (x comma y )equals c x y comma space 0 less than y less than x less than 4, (1)

ioda

(1) Looks like the joint density is

$f_{X,Y}(x,y)=\begin{cases}cxy&\text{for }0$

In order for this to be a proper density function, integrating it over its support should evaluate to 1. The support is a triangle with vertices at (0, 0), (4, 0), and (4, 4) (see attached shaded region), so the integral is

$\displaystyle\int_0^4\int_y^4 cxy\,\mathrm dx\,\mathrm dy=\int_0^4\frac{cy}2(4^2-y^2)=32c=1$

$\implies\boxed{c=\dfrac1{32}}$

(2) The region in which X > 2 and Y < 1 corresponds to a 2x1 rectangle (see second attached shaded region), so the desired probability is

$P(X>2,Y$

(3) Are you supposed to find the marginal density of X, or the conditional density of X given Y?

In the first case, you simply integrate the joint density with respect to y:

$f_X(x)=\displaystyle\int_{-\infty}^\infty f_{X,Y}(x,y)\,\mathrm dy=\int_0^x\frac{xy}{32}\,\mathrm dy=\begin{cases}\frac{x^3}{64}&\text{for }0$

In the second case, we instead first find the marginal density of Y:

$f_Y(y)=\displaystyle\int_y^4\frac{xy}{32}\,\mathrm dx=\begin{cases}\frac{16y-y^3}{64}&\text{for }0$

Then use the marginal density to compute the conditional density of X given Y:

$f_{X\mid Y}(x\mid y)=\dfrac{f_{X,Y}(x,y)}{f_Y(y)}=\begin{cases}\frac{2xy}{16y-y^3}&\text{for }y$

6 0

3 years ago

Is it the first second third or fourth.

svp [43]

It is the first answer

4 0

2 years ago

Read 2 more answers

One! 2+1 = 23 3+1 = 34 4+2 = 26 6+3 = 29 Then 7+1 = ? What’s the answer

Veronika [31]

Answer:78

Step-by-step explanation:

To get first digit 7 ➗ 1=7

To get second digit 7+1=8

3 0

3 years ago

On a number line that is 4 kilometer where is 4/3

Mariulka [41]

Find 4/3 of 4 kilometers...

to do this...

4*(4/3)

^^ this will give you your solution in km

Hope this helps

3 0

3 years ago

Read 2 more answers