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Margarita [4]
3 years ago
13

Kevin's work for deriving the equation of a circle is shown below. x2 + 4x = −(y2 − 20) step 1 x2 + 4x = −y2 + 20 step 2 x2 + 4x

+ 4 = −y2 + 20 − 4 step 3 (x + 2)2 = −y2 + 20 − 4 step 4 (x + 2)2 + y2 = 16 in which step did he make an error in his work
Mathematics
1 answer:
SVEN [57.7K]3 years ago
7 0
We have the following equation:
 x2 + 4x = - (y2 - 20)
 Let's review step by step:
 step 1:
 
x2 + 4x = -y2 + 20
 Answer: OK
 step 2:
 
x2 + 4x + 4 = -y2 + 20 - 4
 Answer: Wrong
 The correct step is:
 x2 + 4x - 4 = -y2 + 20 - 4
 Or equivalently:
 x2 + 4x + 4 = -y2 + 20 + 4
 Answer:
 
he did make an error in his work in step 2
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According to the US department of labor, total employment is expected to increase from 146 million in 2000 to 168 million in 201
saveliy_v [14]

Answer:

The percent increase in the employment from the year 2000 to year 2010 is 15.07\%.

Step-by-step explanation:

Given:

Employment in the year 2000 =146 million.

Employment in the year 2010 =168 million.

To find: The percent increase in the employment.

Solution: We have,

Employment in the year 2000 =146 million.

Employment in the year 2010 =168 million.

Increase in employment =168-146=22 million.

Percent increase =\frac{\textrm{Increase in employment}}{\textrm{Original employment}}\times100\%

Percent increase =\frac{22}{146}\times100\%=15.07\%

Hence, the percent increase in the employment from the year 2000 to year 2010 is 15.07\%.

3 0
3 years ago
Ali scored 58 marks in eng and 49 in math . how much percent in eng more than math​
Sergeu [11.5K]

Answer: 9%

Step-by-step explanation: as all the marks are out of 100 i suppose

so Ali got 58% at eng and 49% at math

so 58-49=9%

and that is how we get the answer

4 0
3 years ago
Read 2 more answers
How would you write 4n + 3 as a verbal expression
Tatiana [17]
<h3>4 times a number increased by 3.</h3>

When we have a number that appears

right before a variable, it means multiplication.

So 4n means the same thing as 4 times a number.

Remember, n is a variable which is just a

letter that represents any number.

Since we are adding 3 to 4n, we can say

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So 4n + 3 can be written as 4 times a number increased by 3.

5 0
3 years ago
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Tracey wants to ride her bicycle at least 150 miles this week. She has already
dimaraw [331]

150 - 42 = 108

108 ÷ 6 = 18

therefore m = 18

hope this helps...

3 0
3 years ago
Can you do 2 and 3 please and tell me how you got your answer?
alexandr402 [8]

Answer:

2. Sorry, I don't how to put that into words, because i'm trying to use calculators, then figure out how they got their answer.

3. C

Step-by-step explanation:

2. ^

3. to get the difference between two numbers, (100 and 50, for example,) you must just simply have them minus each other, like simple math. 100 - 50 = 50.

So your difference between the number 100, and the number 50, are 50.

7 0
3 years ago
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