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3 years ago

VERY URGENT HAVE A TEST TO TAKE

1 answer:

5 0

The easiest way is to try the point (-4,1), that is, x=-4, y=1,
to see which equation works.
b works.

The usual way to do it is to find the equation of the circle
standard form of a circle is (x-h)²+(y-k)²=r², (h,k) are the coordinates of the center, r is the radius.
in this case, the center is (-2,1), so (x+2)²+(y-1)²=r²
the given point (-4,1) is for you to find r: (-4+2)²+(1-1)²=r², r=2
so the equation is (x+2)²+(y-1)²=2²
expand it: x²+4x+4+y²-2y+1=4
x²+y²+4x-2y+1=0, which is answer b.

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lydia buys 5 pounds of apples and 3 pounds of bananas for a total of $8.50. ari buys 3 pounds of apples and 2 pounds of bananas

gavmur [86]

Answer: The price per pound of apples is $ 1.25 and the price per pound of bananas is $ 0.75.

Step-by-step explanation: Given that lydia buys 5 pounds of apples and 3 pounds of bananas for a total of $8.50 whereas Ari buys 3 pounds of apples and 2 pounds of bananas for a total of $5.25.

We are to find the price per pound of apples and bananas.

The cost per pound of apples is represented by x dollars and the cost per pound of bananas is represented by y dollars.

Then, according to the given information, the system of equations describing the situation is as follows:

$5x+3y=8.50~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~(i)\\\\3x+2y=5.25~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~(ii)$

Multiplying equation (i) by 2, we have

$2(5x+3y)=2\times 8.50\\\\\Rightarrow 10x+6y=17~~~~~~~~~~~~~~~~~~~~~~~~(iii)$

and multiplying equation (ii) by 3, we have

$3(3x+2y)=3\times 5.25\\\\\Rightarrow 9x+6y=15.75~~~~~~~~~~~~~~~~~~~~~~~~(iv)$

To eliminate y, we subtract equation (iv) from equation (iii) and we arrive at

$(10x+6y)-(9x+6y)=17-15.75\\\\\Rightarrow x=1.25.$

From equation (i), we get

$5\times 1.25+3y=8.50\\\\\Rightarrow 6.25+3y=8.50\\\\\Rightarrow 3y=2.25\\\\\Rightarrow y=0.75.$

Thus, the price per pound of apples is $ 1.25 and the price per pound of bananas is $ 0.75.

7 0

3 years ago

Read 2 more answers

PLEASE HURRY which expression is equivalent to -6(-2/3 + 2x)

Vesna [10]

Answer:

It's 4-12x

Step-by-step explanation:

3 0

2 years ago

Last week 14 students were given Cardinal Credits for good behavior. This week 22 students were given Cardinal Credits. What was

Dimas [21]

Answer:

$57\%$

Step-by-step explanation:

Given: Number of students who were given Cardinal Credits last week for good behavior = 14

Number of students who were given Cardinal Credits this week for good behavior = 22

To find: percent increase in number of students who were given Cardinal Credits

Solution:

Increase in number of students = 22 - 14 = 8

Percent increase in number of students who were given Cardinal Credits = Increase in number of students / Number of students who were given Cardinal Credits last week for good behavior × 100 $=\frac{8}{14}\times 100=57.14\approx 57\%$

5 0

3 years ago

Help this is my hw from like 2 months ago

madreJ [45]

The answer is y=1/2x+40

3 0

1 year ago

Read 2 more answers

Consider the following frequency distribution.

Zarrin [17]

Answer:

Class interval 10-19 20-29 30-39 40-49 50-59

cumulative frequency 10 24 41 48 50

cumulative relative frequency 0.2 0.48 0.82 0.96 1

Step-by-step explanation:

We are given the frequency of each class interval and we have to find the respective cumulative frequency and cumulative relative frequency.

Cumulative frequency

10+14=24

14+17=41

41+7=48

48+2=50

sum of frequencies is 50 so the relative frequency is f/50.

Relative frequency

10/50=0.2

14/50=0.28

17/50=0.34

7/50=0.14

2/50=0.04

Cumulative relative frequency

0.2

0.2+0.28=0.48

0.48+0.34=0.82

0.82+0.14=0.96

0.96+0.04=1

The cumulative relative frequency is calculated using relative frequency.

Relative frequency is calculated by dividing the respective frequency to the sum of frequency.

The cumulative frequency is calculated by adding the frequency of respective class to the sum of frequencies of previous classes.

The cumulative relative frequency is calculated by adding the relative frequency of respective class to the sum of relative frequencies of previous classes.

4 0

3 years ago