All categories

3 years ago

X=y-1 y=(4-2x) solve by substition

1 answer:

5 0

Since you have an equation equal to both x and y, you can either substitute the equation equal to x for x or the equation equal to y for y.
x=y-1
y=4-2x
I would substitute the y in using 4-2x
x=(4-2x)-1
x=3-2x
3x=3
x=1
Then plug in x and solve for y
1=y-1
2=y

You might be interested in

Ayesha bought a 24-pack of lip gloss for $17.04. What is the unit cost per tube of lip gloss?

NISA [10]

C...................................................................................................................................

3 0

3 years ago

Read 2 more answers

Find the area of this triangle

uysha [10]

Answer:

i think the answer is 67.5

3 0

3 years ago

Rewrite 8y - 1/2 (4y - 16) in a different form

worty [1.4K]

Answer:

8y-2y+8=0

6y+8=0

y=8/6=4/3

4 0

2 years ago

Expand 3(x+ 2.3) Expand 1/3(9x-12)

Snezhnost [94]

Answer:

3x+6.9 and 3x-4

Step-by-step explanation:

since 3 x x is 3x and the sign in the bracket is addition you place it there then place 3 x 2.3

being 6.9.

1/3 x 9is 9/3 and 3 can multiply both sides to get 3/1 or 3 then bring the minus and 1/3 x 12 is 12/3 3 can multiply both sides to get 4/1 or 4

4 0

2 years ago

Listed below are the numbers of heroic firefighters who lost their lives in the United States each year while fighting forest fi

Marysya12 [62]

Answer:

Step-by-step explanation:

Hello!

Data

Year/Firefighters

2000: 20

2001: 18

2002: 23

2003: 30

2004: 20

2005: 12

2006: 24

2007: 9

2008: 25

2009: 15

2010: 8

2011: 11

2012: 15

2013: 34

Common measures of variation

Variance

S²= $\frac{1}{n-1}[sumX^2-\frac{(sumX)^2}{n} ]$

∑X= 20 + 18 + 23 + 30 + 20 + 12 + 24 + 9 + 25 + 15 + 8 + 11 + 15 + 34

∑X= 264

∑X²= 20² + 18² + 23² + 30² + 20² + 12² + 24² + 9² + 25² + 15² + 8² + 11² + 15² + 34²

∑X²= 5770

n= 14

S²= $\frac{1}{13}[5770-\frac{(264)^2}{14} ]$

S²= 60.90

Standard deviation

The standard deviation is the square root of the variance

S= √S²= √60.90= 7.80

Coefficient of variation

Is a relative standard deviation, it is defined as the division of the standard deviation (S) by the mean (X[bar)]. It has not units and is usually expressed in percentage. It shows the variability in relation to the mean.

C.V.= $\frac{S}{X[bar]}$ *100 = $\frac{7.80}{18.86}$ *100= 41.36%

The mean or average is a measurement of position and gives you an idea of the central value of the distribution of the data.

X[bar]= ∑X/n= 264/14= 18.86

Range

In the interval between the max and min values. It allows you to have an idea of the dispersion of the values.

R= Xmax - Xmin= 34 - 8= 26

Xmax= 34

Xmin= 8

Inter Quartile Range

Is the difference between Quantile 1 (C₁) and Quantile 3 (C₃). It shows the 50% mid values of the sample.

IQR= C₃ - C₁= 23.5 - 11.5 = 12

Quantile 1 (C₁) is the value that leaves 25% of the sample below and 75% of the sample above.

Pos1: n/4= 14/4= 3.5

The first quantile is the number between position 3 and position 4

8, 9, 11, 12, 15, 15, 18, 20, 20, 23, 24, 25, 30, 34

C₁= (11+12)/2= 11.5

Quantile 3 (C₃) is the value that leaves 75% of the sample below and 25% of the sample above.

Pos3: n*3/4= 14*3/4= 10.5

The third Quantile is between position 10 and 11

8, 9, 11, 12, 15, 15, 18, 20, 20, 23, 24, 25, 30, 34

C₃= (23+24)/2= 23.5

The measurements of variation don't allow you to know the origin of the data, that it is from consecutive years.

I hope it helps!

6 0

3 years ago